Nah man, it is because the best units never make it online.
My friend who pays far too little for his apartment (gotta love little old lady property owners) has another unit open in the building. The only way you would know that is if you walked past and saw the tiny for rent sign on the door. My friend however, walks past that sign every day and is well aware that he gets an awesome deal from a non-shitty landlord.
If you asked him if there were any good apartments for rent, he would have a good answer. But you gotta always be asking for this to work...if you asked me, I would say no--there's a for rent sign on my building, but the management company is awful and I would never suggest it to anyone at the crazy asking price (and it is advertised on line anyways...since shitty apartments don't sell themselves).