One thing to keep in mind is that not everyone is a great artist. However, their idea may still be a good one, even if the sketch isn't amazing. (Furthermore, many of the great 2d artists are not necessarily good sculptors.) So, someone could have an awesome idea but mediocre sketch, but the idea in the hands of a the right sculptor could end up being awesome.
awesome + mediocre = awesome

Edited by Soupie, 17 June 2011 - 02:08 PM.