Memorability

Splitting usability into first-time users and daily users leaves out the person who opens something once a month. Month-end reconciliation, quarterly reporting, a renewal that comes around twice a year. They finished it last time, so they get filed as someone who knows the product, when in fact they don't remember which button ended it.

That person is in the same position as a newcomer, but the screen treats them as experienced: the onboarding hints are marked as seen and don't appear. The tickets arrive in a different shape too. Not "I don't know how to use this" but "can you tell me how I did this last time." Because these people show up in neither the first-time score nor in efficiency, which measures how fast an experienced person moves, the dimension got a slot of its own.

You measure it by bringing the same person back twice. Give them the task, note the time and where they stalled, then give the same task again two to four weeks later. If the second time matches the first, nothing survived from the first session and the score on this dimension is zero.

Four things hold the score up.

1. Traces left on screen. Recently used items and the settings picked last time, still visible, let a returning person read the screen instead of searching their memory.
2. Names in the words customers use. Put internal shorthand on a screen and this dimension collapses fastest. Someone told what it meant a month ago won't remember a month later.
3. Consistency of position. When a function is always in the same place, people remember a location rather than a path. A redesign takes the largest bite out of this score.
4. A retraceable record. With last month's actions listed somewhere, people open the list and follow the same sequence.

Filling the gap with help articles doesn't work well. Anyone hunting down a help article a month later has already paid the cost. The answer has to be inside the screen for this dimension to rise.

"This screen gets opened once a month, so judge it on memorability."

Use different criteria than for a screen people see daily.

"If last time's selection is still there, they don't have to decide again."

Leaving a trace to hold the score up.

"The redesign moved everything, and the people who use it quarterly can't find it."

Consistency of position broke and the score dropped.

Pagedeck's plan-change screen carried this problem. It opens once or twice a year. Noa brought the same five people back a month later, and three of them took about as long as they had on their first visit; none of them remembered which menu they had entered through.

Mia decided to put the current plan and the date it last changed on the first line of the account screen. In the next round all five went in through that line.