Some exceptions I've seen are cracks where the hands insert into the arms of minifigures and discoloring, particularly on white bricks. And of course there are

Some exceptions I've seen are cracks where the hands insert into the arms of minifigures and discoloring, particularly on white bricks. And of course there are missing pieces, but that's not a quality issue. This summer I bought a set I grew up playing with (#6345 Aerial Acrobats). It sits on my shelf for now but I'm sure I'll play with it with my future children.