Easing is a personality trait

Nothing in the physical world moves linearly. Doors decelerate. Heads turn with intent and settle with care. When an interface animates linearly it isn’t being neutral — it’s being robotic, and users feel it the way you feel a handshake that’s slightly too long.

Every easing curve is a claim about character. A sharp ease-out says eager. A long settle says considered. A spring says friendly — or, overdone, says novelty sock. The curve we ship most is a patient ease-out with a soft landing: confident enough to start quickly, mature enough not to slam the door.

Here is the exercise we run with clients: we show the same card animating with five different curves and ask which one ‘is’ their brand. Nobody has ever said they can’t tell the difference. Most people point at the same one their customers eventually will.

Pick your curve the way you picked your typeface. Then defend it just as hard.