I've seen many questions with the mark [closed] in the title. Does it mean that they will be erased later? Or just remains as closed?
They may be deleted later. It depends on the close reason and what attention they receive (some questions can just go unnoticed). Duplicates which help point the way to other questions (that is, they are worded differently and aid searching) should not be deleted, but many others should.
Users get access to delete and undelete votes at 10k reputation. Moderators (with diamonds) can always delete.
There are many posts on SO.meta about why many others should be deleted; I have neither the energy nor inclination to duplicate that here. The most important point is perhaps the broken window argument: leaving the questions encourages similar questions, and if those simliar questions were desired, the others would not be closed in the first place.– Roger PateOct 29, 2010 at 3:40
2Why would someone deliberately create a new question similar to one they saw was closed? Jun 25, 2012 at 11:25
@EliahKagan because they want to try luck.– BraiamMay 18, 2014 at 16:16