Ideally, two things happen to abandoned questions. Abandonment happens when the user never comes back or in a more permanent manner when the user account becomes deleted. At that point, the text still belongs to the community - so there's nothing preventing someone from re-asking the same question and explaining why having a check mark is important to the community. We have the power to address this, but it seems overkill for the "reward" in most cases. Without any user action, the design for abandoned questions is:
- If they are poor quality, they get edited or down voted - all by user action and user-moderation.
- Answers that are good in the sense that someone searches for the question or answer, finds it and votes it up.
The price of entry to allowing anyone to ask a question is that a regular community member isn't going to ask the majority of the questions. Hopefully, site search is designed to counter act this natural tendency. Your actions of editing the question and adding an answer speak to how abandoned questions can still be cared for.