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Jakob's Law

STR·04 · 4 of 11

People spend most of their time on other sites: they arrive carrying expectations your interface didn't set.

traditional Long-standing practice, with no single citable origin. Why: Nielsen’s formulation is an observation about expectation, not a measured law.

The same task, built twice

Both panes below are real interfaces. They respond, they can be got wrong, and each is timed from your first move in it. The times are not a study — two panes, one reader, no controls. They are here to make a difference you can feel into a number you can see, and nothing is recorded or sent anywhere.

Your task

Open your basket, then close the panel that appears.

Breaks it

Nothing here is broken. The basket is a lozenge on the left, the logo is on the right, and the close control is a word at the bottom. Every choice is defensible on its own and the set of them is unusable.

Keeps it

Logo left, basket top-right with a count on it, close as an × in the panel's top-right corner. None of this is better design — it is the same design as everywhere else, which is the entire argument.

What to watch Where your eye went first, and where your hand went first. You have never used either of these sites; the right-hand one you already knew how to use.

The principle

OriginJakob Nielsen (2000) — an argument about convention, not cognition.
EvidenceThe empirical spine of design systems and platform conventions; the reason the cart lives top-right and search looks like search.
Limits & misuseRead as "never innovate," it would have banned pull-to-refresh and pinch-zoom. The honest reading: convention is a budget — spend your novelty where it pays, and pay the toll of teaching whenever you do.