Why does most hentai look like crap?

Seriously, most hentai looks like it was drawn by a 12 year old. And even if it is well drawn, its animation is either really choppy or the Genitiles are drawn so badly its hard to tell what the fuck they are.

Why is this? Is it just that americans get the shitty hentai?

Is it because most hentai is censored, and must be re-drawn once it gets uncensored and sent to america?

There has to be SOME good quality hentai in Japan.  Like, OAV quality animation comparable to a normal anime series.  Something that captures the detail of a 2D CG image or drawing.  Or the detail of a professional manga artist.  It has to exist.  It must.  I pray to you, hentai God.