Attention, memory and perception
Availability heuristic
People judge how likely or common something is by how easily examples come to mind, so recent and vivid events seem more frequent than they are.
A story you heard yesterday feels more typical than a statistic you read last year. Vivid, recent and personal examples crowd out the rest.
Teams are as prone to it as users: the last angry customer email can outweigh a thousand quiet successes. Look at the data before deciding what's common.
In practice
A team redesigns a feature after one memorable complaint, when analytics show almost nobody hits that problem.
Common mistake
Letting the loudest feedback set the roadmap. Count how often something happens before treating it as typical.
Where it comes from
Described by Amos Tversky and Daniel Kahneman in 1973.