To understand something you have to love it, because understanding is never a completely disengaged stance but springs from inspiration. (Mark Vernon, English philosopher)
OK, that's a bit deep for a Monday morning -- but it's also very true, especially in regard to writing romance. A lot of people scoff at romance, but they still try to write it because it sells and it's got to be easy, hasn't it?
But unless they love the genre, unless they truly get what it is about romance that so many people love, unless reading it fires up their imaginations, they are not going to be able to reproduce it. So... too often they go back to knocking it.