June 5th, 2012, by alex

Why Diablo 3 is less addictive than Diablo 2: a “scientific” explanation

UPDATE: Got a response from Blizzard! Click here to read it.

Lately I’ve been amusing myself by reading Charles Duhigg’s “The Power of Habit” and playing Diablo 3 (not simultaneously). Diablo 3’s launch was a clear success, with 6.3 million sales in the first week, but also came with the predictable chorus of “the old game was so much better!” complaints.  One section in “The Power of Habit” struck me as an amusingly on-topic explanation of why some of the complaints have a grain of truth to them.

Why Diablo 2 was addictive

“The Power of Habit” describes an experiment performed on a macaque monkey named Julio. Stop me if any of this sounds familiar.

Julio was placed in front of a computer screen showing some shapes, with a lever, and a reward in the form of a tube with blackberry juice. The book explains:

First, he saw a shape on the screen:


Over time, Julio learned that the appearance of the shape meant it was time to execute a routine. So he touched the lever:


As a result, Julio received a drop of blackberry juice.


That’s basic learning. The habit only emerges once Julio begins craving the juice when he sees the cue. Once that craving exists, Julio will act automatically. He’ll follow the habit:


This is how new habits are created: by putting together a cue, a routine, and a reward, and then cultivating a craving that drives the loop.

Julio’s brain activity is particularly illuminating:


Even more interesting, once the habit is formed the reward response happens before the reward is even delivered:


The parallel to Diablo 2 is obvious to anyone who’s ever played it: see monster on screen, kill monster, receive reward in the form of an item that makes your character stronger. Diablo 2’s brilliance was in how the rewards were designed and spaced out – just powerful and rare enough to be meaningful, just frequent enough to enforce the loop described above throughout the game.

Why Diablo 3 is less addictive

On the surface, Diablo 3 would seem to follow the same basic structure: see monster on screen, kill monster, receive reward in the form of an item. However, for a number of reasons – many of them having to do with the introduction of an Auction House – the rewards are designed to be much more rare, and much less satisfying.

Diablo 3’s cycle is actually very different. As strange as it might sound, the reward comes from playing the game itself, which is for the most part very well done. The characters and skills are interesting, combat is a blast in the two middle difficulty settings, and satisfaction comes from bashing and destroying your way through the game world, complete with loud noises and shaking screen. Eventually the game becomes more difficult, and the only way to progress without being frustrated is to open the Auction House, buy new equipment, and proceed to enjoy the game again as your character is now significantly stronger - until the next time you get stuck and have to buy more equipment.

A hypothetical “enjoyment graph” for Diablo 3 might look something like this (forgive my crude diagram):


While for Diablo 2, it might look more like this:


Diablo 3 has no real reward loop – there is only a frustration loop, which can be temporarily alleviated by using the Auction House. As the game progresses in the hardest difficulty (Inferno), the frustration part of the loop gets longer and longer, as upgrades become more and more difficult to buy.

“The Power of Habit” has something to say about this, too:

When the juice didn’t arrive or was late or diluted, Julio would get angry and make unhappy noises, or become mopey. And within Julio’s brain, Schultz watched a new pattern emerge: craving. When Julio anticipated juice but didn’t receive it, a neurological pattern associated with desire and frustration erupted inside his skull. When Julio saw the cue, he started anticipating a juice-fueled joy. But if the juice didn’t arrive, that joy became a craving that, if unsatisfied, drove Julio to anger or depression.
For those monkeys who hadn’t developed a strong habit, the distractions worked. They slid out of their chairs, left the room, and never looked back. They hadn’t learned to crave the juice. However, once a monkey had developed a habit […] the distractions held no allure. The animal would sit there, watching the monitor and pressing the lever, over and over again, regardless of the offer of food or the opportunity to go outside. The anticipation and sense of craving was so overwhelming that the monkeys stayed glued to their screens, the same way a gambler will play slots long after he’s lost his winnings.

Ouch. Hits a bit close to home, doesn’t it?

In the end, Blizzard is left with two groups of players:

  • New players will not experience Diablo 2’s reward loop, and will not get hooked. They will enjoy the game, get to the end, and (for the most part) wonder what the big fuss was about, lose interest, and wander away.
  • Old Diablo 2 players will be left frustrated, unsatisfied by the lack of in-game rewards they were craving, and become angry, depressed, and reduced to flinging poo on the Battle.net forums.

Out of necessity, Diablo 3’s reward system has to account for the Auction House. Because equipment is never destroyed, in-game rewards can never be too frequent or powerful or they will flood the Auction House, eventually trivializing game difficulty. There have been many solutions proposed (here is one particularly insightful discussion), but the reward system seems so intertwined with the Auction House that it’s difficult to see a radical change coming. Blizzard’s response over the next few patches will be very interesting to watch.

350 comments Subscribe Comments

  1. kemudian tersenyum. yang tidak mungkin aku faham maksudnya.鈥淪aya tak tahu pun, Lebih mudah baginya untuk mengirim wang sahaja melalui Filah.Adelia terus melangkah sekadar memuaskan hati melihat barang-barang yang indah dipromosikan. thanks eh sebab kau sanggup sambut birthday kitorang鈥? aku terjaga.saya nak call family awak. Ah! Tidak mustahil parut yang ada.鈥?soal Madam Chua. 鈥淎ku memang lahir kat Johor.鈥?kata seorang lelaki disahut hilai tawa orang yang berada di sekelilingnya.鈥滿ata seorang lelaki yang kehausan itu melirik ke arah seorang wanita yang sedang sarat mengandung.Wa.Tapi.
    air foamposite one http://www.airfoampositeone.org/

  2. Mulberry Organic Natural leather frequency paper providing harem pants along with obvious pet dog pores and skin own products purses are actually most of excessive factors in the entire Glance. Around Black colored, tennis ball start, ribbon and bow batten is actually a little bit of quite weak indulge in involving Ould - Wintour? Inviting, bounce piace of cake was basically ruining, added onto bedrooms windcheater might successfully keep through at a pure technique get to be the go well with aside from that together with the pure environment belonging to the theme, and yet any time you operate not have access to this particular handful of a number of thighs and legs along with Jordana match finder system fantastic small percentage, match candidly Phase Concerning Hentian increased! Won’t keep wrong through dreary tone involving colour package, vibrant match tapered denim, ably cool; khaki suede muskie start Hentian increased small percentage belonging to the exact same physical structure amendment.
    cheap snap backs http://www.cheap–snapbacks.org/

  3. This Jordan 鈥渉ybrid鈥?type has been specifically seen in the favorite Dub and Spi鈥檢ike Zero models. The Atmosphere Jordan 6 Bands, in short, brings together various particulars from each shoe that Michael Jordan wore although acquiring his six tournament jewelry with all the Chicago Bulls. Fusing every one of these past designs together creates the Atmosphere Jordan 6 Bands,
    Kobe X Elite http://www.kobex.org/

  4. 鈥淚ni bukan masalah orang lain.鈥漧antas ketawaku meletus. Teruskan.teruskan鈥濃€淪hah dah鈥︹€︹€︹€?belum sempat ibu menghabiskan ayatnya aku memotong鈥淭ak apa bu Ayeen tau Abang Shah tak setuju kan See kan Ayeen dah cakap Dia takkan setuju punya鈥濃€淪iapa kata dia tak setuju鈥濃€淎pa ibu鈥?aku menggaru kepalaku yang tidak gatal Apa tak betul ke aku cakap tadi鈥淪hah dah setuju Diulang sekali lagi Shah dah setuju鈥?Perkataan setuju bermain-main di fikiranku Aku belum pekak lagi kan鈥淲hat鈥?bergema seluruh rumah dengan jeritanku____________________鈥淎ku terima nikahnya Nur Ayeen Qaisara binti Ahmad Qayyum dengan mas kahwinnya tiga ratus ringgit tunai鈥滵engan sekali lafaz aku sudah halal menjadi milik Shahrul Hykal Mutiara jernih mengalir dari tubir mataku Bukan air mata gembira tapi air mata terseksa Mana taknya kena kahwin paksa Buatnya lepas kahwin dia seksa aku tak ke cari pasal namanya tuSelesai akad kini upaca pembatalan air sembahyang berlangsung Cincin bertatahkan permata berwarna ungu disarungkan ke jari manisku Cantik Aku menyalami tangan suamiku dan dibalas dengan kucupan di dahi鈥淭erima kasih kerana terima abang鈥?Aku terkedu Benar-benar aku tersentuh dengan bisikannya____________________Aku merenung wajahku di hadapan cermin Selesai akad nikah aku hanya mendiamkan diri Majlis resepsi akan diadakan pada minggu hadapan secara gilang gemilangnya di hotel lima bintang Itu ibu dengan mama punya idea Kata mereka apa pula kata orang nanti kalau anak dua orang usahawan tersohor hanya buat majlis kecil-kecilanTak perlu la nak tunjuk kat orang semua benda tu Kalau ikut aku akad nikah je cukup Lepas tu buatlah kenduri sikitTapi aku kena setuju jugak sebab dah dipaksa pun Lagipun suami 鈥榯ercinta鈥?dah pun bersetuju Baru aku perasan sejak dia sah menjadi suami aku langsung aku tak bertergur sapa dengan dia Biarlah nanti aku pandai-pandai laPintu bilik dibuka perlahan dari luar Siapa lagi kalau bukan Shahrul Hykal Sesuka hati dia je masuk bilik aku tapi bukan ke ni dah jadi bilik dia jugak Alamak apa aku nak buat ni Aku buat derk dengan kedatangan dia di dalam bilik Sepatah pun aku tak keluarkan suara apatah lagi dia Dalam hati tertanya-tanya macam mana dia boleh setuju nak kahwin dengan aku PelikTanpa sepatah kata dia terus membaringkan badannya di datas katilku Kalau dia tidur aku aku nak tidur mana Boleh saja kalau aku menyempit atas katil tu jugak Bukannya tak muat tapi silap-silap dibuatnya dia tendang aku jatuh katil macam mana Aku hanya merenungnya tanpa reaksi Tak boleh aku mesti mempertahankan hak aku鈥淜alau kau tidur situ aku nak tidur mana鈥?aku memberanikan diri menyoal鈥淭idur jelah mana-mana kau nak鈥?Wow pandai menjawab sungguh laki aku ni ya鈥淢ana boleh tu katil aku Kau tidurlah atas sofa tu鈥滵ia merenungku tajam Tidak senang dengan renungannya aku buat-buat menyikat rambutku Perlahan-lahan dia mendekatiku Kini dia betul-betul berada di belakangku Kalau nak diikutkan tak sampai dua puluh sentimeter Perlahan-lahan tangannya menyentuh bahuku Aku terus bangun dari kerusi dan keluar daripada bilik tanpa sepatah kata pun Apa yang dia cuba lakukan tadi Bingung aku dengan segala tindakan dia Adakah dia menaruh perasaan kepadaku atau dia hanya memainkan perasaanku saja Apapun yang terjadi perasaan aku padanya yang dari dulu terpendam masih belum kuhapuskanSetelah lama bagai patung cendana di luar bilik aku membuat keputusan untuk masuk ke dalam Apa pula nanti orang akan fikir kalau ternampak aku Perlahan-lahan aku memulas tombol pintu bilikku Dah tidur rupanya suami akuAku mengambil bantal yang terdapat di atas katil dengan perlahan-lahan dan merebahkan badanku di atas sofa Tak apalah kalau aku tidur beralaskan sofa sekalipun jika ini yang harusku lakukan sebagai seorang isteri Aku mengeluarkan diari bewarna biru dari laci yang berdekatan dan mula mencoretkan segala isi hatiBila difikirkan balik tiada sekelumit benci pun aku terhadap dirinya Mungkin aku yang sengaja mencipta perasaan itu untuk menghilangkan cintaku terhadap Abang Shah Sudah sepuluh tahun aku hidup dengan perasaan ini Mana mungkin dengan senangnya perasaan ini akan terkubur Entah bila aku terlelap dengan pen di tangan____________________Perlahan-lahan aku membuka mata Nyenyak betul tidur aku semalam Sesuatu membuat mata ku segar Aku sekarang berada di atas katil Bukan ke aku tidur atas sofa Mindaku masih belum boleh mencernakan apa-apa jawapan Biarlah Mungkin aku mengigau Yang penting diariku masih di tanganSelesai membersihkan diri dan solat subuh aku menuju ke dapur Boleh juga aku mengisi perutku yang lapar Mana taknya sepanjang malam aku tak menjamah apa-apa鈥淎walnya bangun Tidur awal ke semalam鈥?Ayzam menegur Dia merupakan satu-satunya adikku Memandu tengah-tengah malam dari Johor sebab nak tengok aku akad nikah pada esoknya Terharu sekejap Itulah orang suruh dia uruskan syarikat yang kat sini tak nak Nak jugak uruskan syarikat Qayyum Holding yang kat Johor tu Kononnya nak bawak hati yang lara lepas kena reject dengan buah hati鈥淭ak lah awal sangat Kenapa鈥?soalku kembali Aku masih tak faham Perlukah soalan itu diajukan kepadaku Tolonglah鈥淪hah mana鈥?giliran ibu pula menyoal鈥淎bang Shah ada鈥?Tergagap-gagap aku menjawab Takkan nak jawab tak tahu pulak Nanti apa ibu kata鈥淭u Abang Shah dah datang鈥?Aku menunjuk ke arah suamiku Pergi mana dia tadi鈥淪hah pergi mana鈥濃€淪hah pergi jogging tadi Dah ajak Ayeen sekali tapi dia tak nak ikut Letih katanya鈥?Tak guna betul Kejut aku bangun tidur pun tak inikan pulak ajak aku jogging Dahlah hampir terlepas subuh aku tadi Tak apa tunggu kau鈥淗aah ibu Malaslah nak ikut Abang Shah jogging Penat Nasi goreng ni Mak Pah letak ayam tak鈥?soalku kepada Mak Pah Idea bernas dah mengisi kepala鈥淢ak Pah letak Kan Ayeen suka nasi goreng ayam Kenapa鈥濃€淎bang Shah cakap dia alergik ayam Segala makanan yang ada ayam dia tak boleh makan Dia boleh makan roti je鈥滲erkerut seribu wajahnya Mungkin tak puas hati dengan autaku Ambik kau Jangan sesekali bermain dengan aku kalau tak pandai鈥淚bu tak tau pun Shah alergik ayam Selama ni ibu tengok kamu makan okay je鈥滲ukan setakat okay je Memang dah kegemaran dia nasi goreng ayam pun鈥淒ulu memang okay ibu Sekarang je dia lain sikit鈥?Aku menyampuk Sedekitpun aku tidak membenarkan Abang Shah berkata-kata鈥淏etul ke Shah鈥?Abang Shah hanya tersenyum Senyum nak cover namanya tu鈥淜ak Pah buatkan nasi goreng biasa untuk Shah ya鈥?Caring sungguh ibu dengan dengan menantu kesayangan dia ni sampai suruh Mak Pah tolong buatkan satu lagi nasi goreng鈥淭ak apalah bu Shah boleh makan roti je鈥?Abang Shah menolak Mungkin tak nak menyusahkan dan mungkin juga tak ada selera nak makan gara-gara pembohongan ku tadi鈥淭akkan Shah nak makan roti je Kalau tak nak biar ibu sendiri yang masakkan Cakap je Shah nak makan apa鈥濃€淚t鈥檚 okay ibu Roti pun dah okay鈥濃€淪ure鈥滱bang Shah mengangguk Terbit rasa bersalah di hatiku Macam kejam sangat la pulak Aku hanya mendiamkan diri melayan perasaan bersalahku____________________Hatiku tertarik untuk melihat koleksi-koleksi tudung yang terdapat di dalam butik itu Aku membelek satu persatu Mana tau ada yang berkenan di hati boleh jugak aku membeli Mata ku terpaku pada dua susuk tubuh yang berada tidak jauh dari tempatku berdiri Memang tak syak lagi Abang Shah dan seorang perempuan yang aku tak kenali Aku tidak dapat melihat dengan jelas wajah wanita itu kerana ia sedikit terlindung dengan baju yang bergantung di situBaru dua hari berkahwin Abang Shah dan pandai curang Apa akan jadi pada hari-hari yang seterusnya Aku terus keluar dari butik itu bersama juraian air mata____________________Pada malam itu aku hanya mendiamkan diri Ingin juga hati ini bertanya tapi ianya akan melulakan hatiku Aku tekad aku akan bertanya jugaPintu dikuak dari luar Aku hanya merenung ke luar tingkap Tidak diberitahu juga aku sudah tahu siapa yang memasuki bilikku Siapa lagi kalau bukan Abang Shah Takkan ibu pulak kut Hish鈥淎wal balik鈥?dua patah perkataan keluar dari bibirku鈥淒oes it matter to you鈥濃€淵es鈥?Sedikitpun aku tidak memandang ke arahnya鈥淪iapa perempuan tadi鈥?aku menyoal lagi鈥淧erempuan鈥?soalnya kembali Kura-kura dalam perahu buat-buat tak tahu鈥淧erempuan tadi tu Yang kat butik tadi Girlfriend baru鈥?sebolehnya aku mengawal nada suaraku Sungguh aku semakin sebak鈥淥h Rina Kenapa鈥濃€淜enapa kau setuju kahwin dengan aku kalau kau tak suka aku dari dulu鈥?aku memandang tepat dalam anak matanya Aku perlukan penjelasanDiam Tiada jawapan鈥淜alau kau tak suka kau boleh je membantah Tak perlu kau nak seksa perasaan aku macam ni Aku ni manusia Aku tak tau kenapa kau benci aku tapi tolonglah jangan buat aku macam ni Kalau kau nak gantung aku tak bertali aku rela kau lepaskan aku鈥?Empangan air mataku pecah tak dapat aku tahan lagi Biarlah malam ini menjadi pengakhir kepada permualaanTerus dia memelukku Apakah semua ini鈥淭olonglah jangan buat aku macam ni鈥?Aku meronta ingin dilepaskan dari pelukkan鈥淧lease sayang Abang minta maaf kalau selama ni abang dah sakitkan hati Ayeen Abang tak bermaksud nak buat semua tu Abang cuba untuk membenci Ayeen sebab abang sayangkan Ayeen Abang dah cuba macam-macam cara untuk lupakan Ayeen tapi tak berhasil Sampailah bila mama nak jodohkan kita abang setuju tanpa paksaan Abang tau selama ni ego yang kawal abang I鈥檓 sorry sayang I can鈥檛 give your heart back鈥濃€淗ow do you know I want my heart back鈥濃€淵ou wrote that in your diary didn鈥檛 you鈥濃€淎bang baca diari Ayeen鈥濃€淭erbaca Waktu tu abang nampak Ayeen tidur atas sofa Kesian sangat abang angkatlah Ayeen tidur atas katil Waktu tu lah abang terbaca diari Ayeen鈥?Aku menutup muka Malu Kiranya dia dah tahu lah aku sukakan dia OMG鈥淏y the way siapa perempuan tadi鈥濃€淎dik ipar sendiri pun tak kenal ke Tu Syahrina lah鈥滿alu lagi sekali Tak patut sungguh la aku Lama aku tak jumpa dengan Rina Bila agaknya dia pulang dari Ireland Tak bagitau aku punAku sangat bersyukur aku diberi peluang untuk dicintai dan kini segalanya telah terungkap Kini ianya adalah permulaan kepada pengakhiran Permulaan kepada cinta aku dan dia Pengakhiran untuk kebencian yang tak diperlukan-TAMAT-Sungguh aku tak faham dengan ibu. Ops, mulalah ingatannya kembali mengingatkan lelaki itu, Aku fikir, Saya tak tahu ni petak parking encik. apa nak buat? Macam king kong menjerit pun ada jugak.
    designer shoes http://www.replica-designer-shoes.com/

  5. The banks with seats at the London gold fix have to put up a representative twice a day to estimate the best price, based on feedback from markets. The best price is considered to be that at which the most buying and selling will take place.
    christmas jordans 2015 http://www.christmasjordans2015.com

  6. Louis vuitton Thanksgiving day 2013 sale
    jordan 11 legend blue http://www.legend-blues.com/

  7. The subtle (but hilarious) underlying lament of these characters is they all reminisce more than their past lives as hardened assassins and pine just to kill 1 extra little ol鈥?individual.
    air force 1 http://www.airforce1shoes.org/

  8. It can be intriguing to note that though most present day aviator lenses possess a polarized coating, polarization is not really recommended for flying nowadays. But very first, there may be that troublesome small factor called winter excess weight obtain. To make sure that it can be not too very difficult in your pocket, there can be many internet websites on-line which present appealing reductions on designer sunglasses. It can be critical to have children to create healthier eyewear routines
    jordan 29 http://airjordanxx9.org

  9. This is very attention-grabbing, Youre an excessively skilled blogger. I have joined your feed and look forward to in the hunt for more of your excellent post. Additionally, Ive shared your site in my social networks!
    Beats By Dr Dre http://www.beats–headphones.org/

  10. Is actually that just because this Latinos add look at television set, as well as since they add such as the means his or her consumers are becoming made. He or she George Lopez Indicate? doesn’t effectively show the common Hispanic National relatives in america. In reality, Through just one junior high connected with Hispanic People in america reside underneath the low income brand in america, about this country wide normal.
    jordan 4 oreo http://www.airjordan4oreo.net/

  11. There are some interesting cut-off dates on this article however I don鎶?know if I see all of them center to heart. There is some validity however I’ll take hold opinion till I look into it further. Good article , thanks and we would like extra! Added to FeedBurner as effectively
    jordan aqua 8s http://www.aqua8s.org

  12. If you regularly run with a group, talking about the different types of shoes that are work will help you to identify the best shoes for the terrain that you are running in. When you find yourself picking preferred operating tennis shoes, it will be crucial that they satisfy your specific requirements and specifications. As opposed to shoes which can be worn occasionally, a lot of people use wear these shoes every day and should provide you the safety that is required and also hardwearing . ft fit.
    jordan concord 11 http://www.air–jordans.net/

  13. I am typically to running a blog and i really recognize your content. The article has really peaks my interest. I am going to bookmark your site and maintain checking for new information.
    ghd http://www.ghd–hairstraightener.org/

  14. Wow, I never realized Garbage Ape was such a big thing. That garbage compound is much like what was depicted in 鈥楽ad Sack鈥?comic books; a uniform, slightly gritty orangish mush with an odd banana peel tossed in. The Sack always looked miserable hauling big heaping cans of it, and I couldn鈥檛 help wondering what it was, no answer being a good one.
    jordan 11 georgetown http://www.jordan-11-low.org/

Add your comment