Number of choices per page
Kathy Sierra has a very good post on how poor user experiences deplete our cognitive resources.
If your UX asks the user to make choices, for example, even if those choices are both clear and useful, the act of deciding is a cognitive drain. And not just while they’re deciding… even after we choose, an unconscious cognitive background thread is slowly consuming/leaking resources, “Was that the right choice?” […]
If our work drains a user’s cognitive resources, what does he lose? What else could he have done with those scarce, precious, easily-depleted resources? Maybe he’s trying to stick with that diet. Or practice guitar. Or play with his kids.
This is a useful reminder that every choice in an interface has a cost, even when the options are clear and reasonable. Designers often treat choice as generosity: more filters, more settings, more routes through the same task. The user experiences it as work.
That work does not end at the edge of the screen. A bad interaction can leave someone with less patience, less focus and less capacity for whatever comes next. Our designs echo beyond our applications, which is a slightly uncomfortable thought.
It should be.