Well, I personally don't write romances at all, but from the things I've seen from other works, the issue with romances is that the reason they seem cliche is because just about every possible avenue you could take with a romance story has been done to death. However, I don't think overuse is necessarily the problem; to me, the real problem is that there's surprisingly very few people out there who can write romance well, so that makes it look like romance is a bad genre when the reality is that most people just don't know what love is :P