[olavk]

They only close for writing answers to the question, the question (and answers written before it was closed) is still up with a link to the duplicate.

The asker can edit the question to provide more information and the question can be nominated for reopening. It only requires 5 votes to reopen, IIRC.

[s73v3r_]

But why? What's the point of all those hoops, other than to discourage new users?

[olavk]

Well if the question is a legitimate duplicate then it is clearly a win for everyone, not least the one asking the question, since now you have a link to answers to your problem which have already been written. Which means now your problem is solved.