I was going to retag a question but it didn't have the link. Also the edit link was grayed out. It is 31 minutes old and I have they are there on other questions. What situations does this happen in?
1It probably had a pending suggested edit.– MysticialJul 19, 2012 at 19:40
Which question?– user102937Jul 19, 2012 at 19:40
2Other situations: full suggested edit queue, temporary edit ban because of too many rejected edits.– Daniel FischerJul 19, 2012 at 19:41
It came back now but it was stackoverflow.com/questions/11567632/… maybe because jumpnett was editing it, though it shouldn't have taken more than a few seconds to add the one tag he did :S– CeleritasJul 19, 2012 at 19:47
3@Celeritas That had to be approved, that took a couple of minutes. stackoverflow.com/suggested-edits/322861– Daniel FischerJul 19, 2012 at 20:01
Hover over it. The link will tell you.
It's in the hovertext.
:) As mentioned in the comments, it can happen for many reasons, most likely the edit queue is full. The link used to be removed completely, but a recent feature change leaves it on the page, greyed out.