Edit:
Also, just to add. Something that I may do if I am an "in and out" guy. On a thumb your image quality may look fantastic; HD because it's obviously a small image thumbnail... BUT when I come into your room, even if I have it on your highest quality setting, it may be fuzzy or grainy etc so then instantly I may go. I learned a long time ago not to "annoy" the model with a "hey do you know your cam quality is bad?" because I have had my hands bitten way too much from it. I understand why (everything depends on circumstances and money etc). But yeah, that might be what SOME are doing, but I would maybe only do it a couple times for a model BUT it wouldn't be every day or "often".. It'd be weeks apart, because my thought process might be that you may have upgraded and improved OR simply I forgot after a month or 2 lol.