This question already has an answer here:
Bolstered by evidence from How to Solve the “New Users Who Don't Return” Problem?
It's a common problem across the sites that users -- new, old, and apathetic -- will sometimes leave their question without accepting an answer for an inordinate amount of time (usually to the extent of "ever").
I thusly request adding an answer acceptance timer or an option for those with enough rep to vote to accept an answer.
While some questions have no immediate answers (like questions about plot elements in unreleased films), many questions have clear and decisive answers that deserve commendation.
Perhaps tying it to the number of votes for the existing answers? Surely a bad answer - which the asker could change if they ever returned -- is better than no answer at all.