I've contracted a designer before (an HNer, mind you) that literally told me that he was working on the design for about 3 weeks, without showing me any form of progress whatsoever. On the last day we were working together, he said, "I've been busy, and I haven't had time to work on it. Find another designer." He had been jerking me around the entire time without doing an hour of the work, and later admit it.
This has happened on more than one occasion. He had a brilliant portfolio.
The ones that are difficult aren't difficult because they give me opinions; in fact, that's what helps to make a great designer. I like creative people that come up with their own ideas.