Choices and persuasion
Decision fatigue
The idea that making many decisions in a row wears people down, so later choices get worse or are avoided altogether.
Long forms and sequences of choices tire people out. By the end, they accept defaults, skip optional steps or leave.
Ask for fewer decisions: pre-fill what you can, set good defaults, and put the important choices early, before people are tired.
In practice
A checkout that asks for shipping speed, gift wrap, insurance, a membership and a donation in a row loses people somewhere in the middle.
Common mistake
Leaning on the science too hard. The theory behind it, ego depletion, failed a large replication across many labs in 2016, so treat it as a useful design heuristic rather than settled fact.
Where it comes from
Grew out of Roy Baumeister's research on ego depletion from 1998, and was popularised in Willpower (2011), written with John Tierney.