Odd replying to a 7 month old post but at least I have an answer now.
If your comments get downvoted a lot, your reputation sinks and you have to wait a small period of time to post comments.
And while this was made to keep people from spamming offensive comments, it has one teeny tiny, yet so crucial flaw-
People can mass downvote your comments to intentionally give you the comment timer. No reason needs to be given, and it can happen to anyone.
This info may be outdated because the reputation system was disliked and may have been removed.