Creatures of Convention
November 10th, 2005
I remember when I was in grade school, I was baffled by my teacher’s insistence that I spell the word “thief” correctly. What got me puzzled was I spelled it “theif”, yet she recognized it immediately and knew what it was (enough to correct it). Since I had communicated the word I wanted, what was the difference if I spelled it wrong? It wasn’t for many years until I understood the answer to that question.
We are creatures of convention. When something doesn’t match our expectations, we have to stop and spend more cognitive energy making it fit into our world.
Take this sign I stumbled upon at a local Baskin Robbins:
4.8 is the same as 4.80, when talking about decimal numbers. Yet, what does $4.8 mean?
In many contexts, people naturally expect money to be represented a certain way. In the US, the convention of showing two decimal points after the dollar amount is what people expect. Anything else makes people stop and think for a second. (In other parts of the world, a comma (‘,’) commonly is swapped in meaning with the period (‘.’), so 23,480.10 would be represented as 23.480,10.)
When we run into something we don’t expect, it causes us to stop and change our cognitive focus, albeit for just a moment. Typos can have the same effect. While we almost always can deduce the author’s intent, the act of decoding the word stops us from considering the meaning of the sentence and makes us consider the meaning of the word. Only when we’ve done that, can we get back to the sentence.
The extra time it takes slows us down and makes us less efficient. This is why spell checking your content and making sure you’re following conventions people need are important.
(By the way, don’t confuse convention with consistency. A consistent interface may follow common conventions, but it may not. And something that is consistent without being conventional doesn’t help the user, usually. Left navigation, while frequent, is not yet a convention because it just hasn’t been around long enough. That’s why we can say right-side navigation is just as good.)
November 10th, 2005 at 4:19 pm
At what point has something been around long enough to be considered ‘conventional’? Is it a proportion of the total time a ‘thing’ (such as the web) has existed? If so, it’s safe to consider left hand navigation a convention.
Recognising left hand navigation as a convention does not preclude right hand navigation from also being a convention (albeit a convention that has been significantly socialised by blogging software default layouts).
Identifying something as a convention requires that the experience of the thing is common to a community. The size of that community may vary. For example a word may take on meaning that is specific to a region (dialect), ‘Bad’ has both a formal and colloquial meanings. If the word is used consistently, e.g. to mean ‘good’ a person from outside of the community will gradually become aware of the new, context-specific meaning. Consistent use leads to an understanding that may be thought of as conventional.
If there’s one thing usability evaluation reminds you of, its that people learn. We draw on our previous experience when engaged in any activity, including using websites. Consistency enables a system to be learnt. Consistent use of conventions requires less learning as it drawns on prior experience. Inconsistent use of convention is likely to be frustrating. (For example, when underlined text does not denote a link.)
As to right hand navigation ‘being just as good’, without context (i.e. what is meant by ‘good’), such as statement is meaningless. Good as/for what? If by good you mean ‘efficient’ this article on the evaluation of navigation using eyetracking software may provide further food for thought.
November 10th, 2005 at 4:56 pm
Sorry Andy, but I disagree: Consistency is the Wrong Approach
(Even the eye tracking article you provide says so. Just read the bulleted tips at the bottom. They say the intent and context of use far outweighs any consistent use of contextless layout convention.)
November 11th, 2005 at 8:25 am
When did ‘what people know’ become different from ‘consistency’? I always understood consistency to mean: consistent with the knowledge (expectations) of the user base.
“Don’t Make Me Think” come to mind.
November 11th, 2005 at 8:49 am
It depends on who is using the word ‘consistency’. Many people interpret it to mean “make things look and behave the same as other things” — independent of what the user knows or needs. (For example, “we need the same navigation across all of our sites” or “we always use ‘OK’ and ‘CANCEL’ on all of our forms.”)
On the outset, this feels like it works for the user, but, as the design inherits any amount of complexity, it quickly starts working against the user and the effectiveness of the design.
November 16th, 2005 at 6:43 pm
Hi Jared,
We’re not in disagreement. If you create an interface with reference to the user’s existing knowledge you are drawing on the conventions they are familiar with. Across a single site you would then (hopefully) maintain consistency. For example, a convention might be logo in the top left of the screen will link to the homepage. To be consistent, this behaviour would be maintained throughout the website.
Consistency does enable a system to be learnt: push lever, get peanut. Adhering to conventions reduces the cognitive burden of learning a new system: last time I pushed the lever I got a peanut, this time I push the lever expecting a peanut, if I get a peanut-great, if not I’ll need to learn a new system.
The worst case is when a convention known to the user is either misused or used inconsistently. This introduces uncertainty. I push the lever once, I get a peanut, twice a lemon, etc. etc.
It’s not necessary to adopt a binary approach to conventions and consistency. They’re complementary approaches/considerations.