Many times when looking at a topic I will think its closed because it has [closed] in the title, only to realize its been moved from another stackexchange board.
To expand on @jeffs answer.
If, say, a question is migrated from Stackoverflow to Programmers. The Question is Closed on Stackoverflow and then the link redirects to Programmers.
Not entirely sure how the system works (Its possibly documented somewhere on meta.se).
I myself have a question I asked on SO. I asked a mod later to move it off to programmers. So it shows as a normal question here, but the question shows on my list of questions on my profile with [closed] in the title.