Elements of Simplicity

What it is

Ability is not a property of a task. It is a relation between a task and whatever a particular person is short of, and the six elements are a checklist for finding out which shortage is operating. Time. Money. Physical effort. Brain cycles, meaning the mental parsing a thing demands. Social deviance, meaning how far the behaviour departs from what the people around you do. Non-routine, meaning how far it departs from what you already do without thinking.

The list is the useful half of a bigger model. In B. J. Fogg's behaviour model, written B = MAT, a behaviour happens only when motivation, ability and a trigger arrive together and with enough force. Miss one and nothing happens. The argument that made the model into an industry is about which of the two levers is worth pulling: motivation is expensive to build, slow to move and actively resisted by the person you are trying to move, while friction can simply be taken away. Removing steps converts intent that already exists. That asymmetry is the engine underneath most of what a product team does when it says it is improving conversion.

Two of the six are almost never audited, and they are the two that do not show up in an analytics funnel. Teams instrument clicks and load times, which covers time and physical effort. Nobody instruments the moment a user cannot work out what a screen is asking, which is a brain-cycles cost, and nobody instruments the moment a user decides a thing would be embarrassing to be seen doing, which is a social-deviance cost. Both make the behaviour not happen. Neither leaves a trace in the data.

The attribution is unresolved and this page says so rather than picking a side quietly. Our own note's definition calls these B. J. Fogg's six factors, and our audit of Hooked records B = MAT as Fogg's model with the six elements as Eyal's elaboration on it. The note's frontmatter, meanwhile, names Nir Eyal as originator with a confidence of "high" and a year of "unknown". That exact shape, a confident originator with no date, is the signature this vault has learned to distrust, because it is how five misattributions got in: whoever was writing reached for the nearest author already in the vault rather than the one who did the work. The safe reading is that the ability term and the model are Fogg's, the formulation quoted everywhere is Eyal's presentation of it in Hooked (2014), and the exact split has not been settled here.

The evidence position is simpler and less comfortable. This page is tagged unreviewed, which records that nobody here has assessed the six elements against a literature, and there is a reason for that beyond laziness: there is no literature to assess. The list is a taxonomy. It cannot fail replication because nobody built it as an empirical claim. It is worth using, in the way a good checklist is worth using, and it is not evidence that anything is true.

What the framework does earn is a reversal, which is the most interesting thing about it. The same six levers work in either direction. Effort pacts are the ability term run backwards, adding friction to a behaviour you want less of rather than stripping it from one you want more of, and Eyal wrote both books, the one about removing steps and the one about putting them back, without ever drawing the parallel to his own framework.

In effect

Research: the nearest real literature, and what it does not cover

There is no study of the six elements. The nearest genuine research neighbour is cognitive load, the finding that working memory has a narrow channel and that most interface demands are extraneous to what the user came to do, which is a real experimental literature with its own limits. Brain cycles is the design vocabulary for the same cost, and the translation is close enough to be useful and loose enough to be worth flagging: reducing load is reducing friction, but a load-theory result is about learning, and a brain-cycles judgement is usually about a checkout. The asymmetry is worth stating. In teaching, load is cut so the learner can spend the capacity on the harder work. In commerce, load is cut so the user does not stop. The two motives recommend the same interface and answer to different people.

Borrowing the credibility of the first for the second is the move to watch for, and it is made constantly in design writing.

Everyday life: the photograph you would not otherwise have taken

Before the lock-screen camera shortcut, taking a picture on a phone meant waking the device, unlocking it, finding the app and waiting for it to open. Each step is small. Together they are a non-routine cost, which is the element that decides whether a behaviour is something you do or something you would have to remember how to do, and it is paid at exactly the moment when the thing worth photographing is still happening. The shortcut did not make anyone want to take more photographs. It removed the reason not to, at the only moment that mattered.

The same element explains why a habit survives a house move badly, and why an app that was fine yesterday feels like work on a phone you have just replaced.

Commerce and product design: Twitter's homepage, and the ease curve of publishing

The clearest single case is Twitter's own redesign between 2009 and 2012. The 2009 homepage tried to raise motivation, explaining what the service was for and why you might want it. The later one stopped pitching and cut the signup down instead, once the company had worked out that engagement came from following people rather than from being persuaded. Same product, opposite lever.

The wider pattern is the ease curve of publishing. Blogger asked for time and a non-routine skill, since writing and formatting a post is a thing most people do not know how to do. Twitter cut the time cost by capping the format at 140 characters. Pinterest, Instagram and Snapchat cut it further by replacing composition with a photograph and a tap. Participation went mainstream at each step, and at no point did anyone become a better writer. Google's plain one-box homepage beat Yahoo, Lycos and AltaVista on brain cycles alone. Pinterest's infinite scroll removed the small physical-effort cost of clicking through to the next page. Facebook Login spread by saving brain cycles at a signup form, one click against a form, and it charged for that saving in a currency most users were not equipped to notice they were spending, which was a privacy decision made in passing.

That last one is the honest shape of the whole practice. Friction removal is not neutral, because the step being removed is sometimes the step where the user would have thought about it.

What it does not say

It does not say the six elements have been tested. They have not, by us or as far as we can establish by anyone. This is a framework with a design record rather than an evidence base, and the unreviewed tag on this page records our own position rather than a verdict on the idea.

It does not say the list is exhaustive or the categories clean. Brain cycles and non-routine overlap heavily. Social deviance and money can be the same cost wearing different clothes. The value of the list is that it makes you ask which shortage is operating, not that the six are separable in any measurable sense.

It does not say simpler is better. Every case above is a case of a company removing a step because the step was losing them users, which is a business argument that happens to coincide with a usability one. Where they diverge, and the Facebook Login example is where, the practice follows the business. Anyone using this framework on their own product should expect it to recommend whatever increases completion.

It does not belong to Eyal alone, and possibly not to him at all. See above. Credit for the model goes to Fogg. Credit for the six-element formulation is unsettled here and should not be asserted either way in a published piece until it is.

Who developed it

B. J. Fogg built the behaviour model, B = MAT, that the ability term belongs to. Nir Eyal presented the six elements in Hooked (2014), ch. 3, and that presentation is the version in circulation. Whether the six-factor breakdown is Fogg's or Eyal's elaboration on Fogg is recorded inconsistently in our own vault and has not been resolved. Neither man has a page on this site yet.

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