because if you don't, here's how:
1. click on the "thread not working? click here to rebuild"
2. reply to the thread. I usually just reply with "rebuild" but you can write any reply.
I swear I rebuilt about 10 threads yesterday. I'm feeling a bit like the DiS equivalent of the housemate who passively does everyone else's washing up! (But of course this could just be my perception and the threads could just mess up so often that we each have to rebuild them about ten times a day).