We used to have a feature here that helped with that, the accept-percentage below each questioner's user-badge. They went away about a month ago since they were causing more harm than good; people were refusing to answer questions from askers with low percentages and that's not what we're about.
Such a notifier does exist for brand new users. When they upvote an answer on their question, there is a popup that suggests that if its good enough, click Accept. Not all askers even bother to upvote though.
And finally, we have a dual feedback system here. Askers can Accept answers, and the rest of us vote for the one we think fits best. Sometimes these are two very different things; as a Moderator I occasionally get a flag worded like:
The accepted answer is wrong, completely wrong. It should be unaccepted.
Which I can't do a thing about. Only one person can Accept an answer.
Don't look to the Accepted flag as your sole source of truth.