Stack overflow is about getting high quality answers quickly. The way that answers are sorted is intended to help realize that goal. However, occasionally low quality answers find themselves on the top, when an answer is accepted, but later turns out to be unsupported by the community at large.
For example, the accepted answer to this question has -4, while the highest scoring answer has a score of 19. Without even looking at the contents of the responses, it's probably the case that the information in the accepted answer is dangerously incorrect while the most valuable info for future travelers is hidden further down.
This can amount to a lot of noise before finding value:
In a lot of cases, this happens when a one time user accepts an answer and then leaves, never to be seen of again. This has its own set of issues addressed in other questions. However, users who are still active are well primed to help improve answer quality, but currently have no one of knowing that their accepted answer has become dated.
In this particular case, the asker is still an active SO participant:
If prompted, they might be so inclined to revisit their question.
We don't need to pressure people into always accepting the highest voted answer, but in extreme cases they can help improve quality answer visibility without undermining the current sorting system that places the accepted answer at the top.
This would address something similar to what is currently being handled with the reminder:
Have you considered accepting an answer or starting a bounty for this question?
A good threshold might be sending a reminder to the question owner whenever the populist badge is earned on a given question. If they dismiss it, they don't need to be reminded again, but it's a good opportunity to allow active users to reconsider accepted answers that might have become incorrect.