It's often not the doc but the person answering the phone or the person responsible for calling back the patient who drops the ball. I have had this happen in several offices.
I mention to my docs when I do not get call-backs, and I have heard some of them chew out the phone people right away - like the time I reported an infection a few days after a hand operation and got no call-back. I treated it myself before it could get serious. The doc got mad at the staff, and chewed them out on the spot, because he was in the office and would have had me come right in!
I'm not forgiving a doc who is chronically unreachable, but choose the doc you think is best, who's medical judgement you trust, and knows you. Then ask why he is unreachable, why you didn't get the callback ... If you don't trust any of them medically, then jump to a new one.