I've read the answer listed here, but I still have a few questions. When a question is marked duplicate, it is marked with [Duplicate], but what does that do? (For reference check this question.) The question is marked as [Duplicate], and no Answers can be added, but other than that, no changes are made. Edits can still be made, comments can be added, and votes can still be made. I have seen questions that have been marked duplicate that quickly disappear and I guess my question is why some of these questions stay on the homepage for an extended period of time instead of just getting closed permanently