When a question I voted to close gets reopened, I cannot vote to close it again, because everybody can vote to close a given question successfully only once. I understand this as it avoids close wars and similar abuse.
However, in this situation, I can not even flag to close. I can only flag as spam/offensive or flag for moderator attention. While moderators can deal with this, they can only do so with a unilateral vote but have no option to just send it to the close queue. Also, moderators need not necessarily be bothered with this.
In the following situations, flagging such a question would make sense in my opinion:
- I vote to close a question as unclear. It gets clarified and reopened, but through the clarification I can see that it’s a duplicate.
- A reopened question is rendered closeworthy by a change in site policy.
- A user nominates a question again and again for reopening until they succeed by chance. This happened with this question (first, second and third attempt). While this particular question should arguably have been discussed on Meta before another attempt for closure (and another solution was found anyway), this situation is also prone to abuse by particularly stubborn users.