I loaded a post, there were already 4 close votes. I felt it should be migrated, so I clicked the close link to bring up the options but received a message similar to
You can only open the close box every 3 seconds
I waited 5 seconds, clicked again, same issue.
I refreshed the page and realised that I was on a different SE site, so obviously whilst I was on the site reviewing the question, some one else pushed the final close vote. The message I was seeing was not an accurate description.
It's a tiny bug but a bug is a bug so thought I'd flag this!