Peak-end rule
The peak-end rule is the finding that people judge an experience by its most intense moment and its final moment, not by the average of the whole.
How it works
Memory does not keep a running total. It keeps a couple of snapshots, and two of the slots it reliably fills are the extreme and the ending. Competence in the middle is largely invisible, because it matched the prediction and cost nothing to store. That makes the last minutes of any exchange worth far more than the same effort spent anywhere else, which is why a small unearned pleasure on the way out is remembered when the main event is not, and why a wait at the very end taints an otherwise good evening. Nothing in the source establishes how large the closing gesture needs to be.
What it changes for a personal brand
Find the last thing that happens to someone who deals with you: the final email in a sequence, what appears after they subscribe, how a project ends. Remove the wait you have not noticed there, then put something deliberate in its place. It is currently doing nothing, and it is one of the two moments they will keep.