>>6659530A good looking custom doll is easy if you aren't a poorfag and willing to shop around. The character might still be a dumb af one but you don't see that on pictures. Getting some nice clothes, wig, eyes, and a proper face-up is no rocket science. Doesn't have to be any super special creative concept or whatever either.
Lots of people just lack "the eye" though and don't understand how to learn and be inspired by the works from others.
Putting together a custom for an existing media character is hard, simply because it's cosplay in really fucking small. You are forced to do it yourself or commission someone, and many seamstresses don't like doing that kind of stuff. Extra points when you buy a doll that actually nails the face/body and really looks like a tiny version.
Sure, you skip the "need to design myself something" part, but eh.
Buying a full-set of any kind is easy mode, doesn't matter if it's generic doll full-set or that Volks DD full-set of waifu XY.