I certainly agree that doing something for charity does not mean unloading trash, but none of us has more than 24 hours in a day, and in some situations quantity does get a little priority over quality. I'm not saying that I would donate something that I'm ashamed of, but I most certainly feel I should give more of my effort to things for my loved ones.
As others have pointed out, a person who is cold will be glad for a quilt that is warm. Quality of workmanship and materials is important only in so far as it affects the functionality of the quilt - definitely 1/4" seams, for example.
Seriously, if you can make several simple quilts in the time it might have taken to make one special one, which would be preferred by the ones standing in line for them? That said, I try to give the best I can at the moment, and I try to put some thought into each one.
Another thing I sometimes do is try something new that I may not have quite mastered yet. I hope the recipient recognizes my human frailty and desire to do something special, even if the result is less than perfect.
I would not want to see a newbie quilter hesitate to make a charity quilt because of a fear that it might not be good enough.