I see where you're coming from, but there is 0, and I do mean ZERO, chance that all the players we scouted/were offered/etc. were actual crap.
Moyes also has a type of player he goes for (older/"experienced"), and a way he operates - late, cautious, until the final second. When you do your business that way you'll end up with fewer chances and options as most are gone by then, and if you're known to operate that way, then yes, people will probably not want to deal with you a lot. That's how you end up with a Barry*/Aznou late in the transfer window, etc., etc.
I get you defending him and that's fine, but we don't need to move mountains to prove how amazingly great Moyes is at everything when he's clearly flawed and has been since he entered the PL with us 20something years ago in many things and those flaws are widely known.
E: Barry might be a bad example, think he joined/was confirmed mid-july? Or something, not sure.