Philip Roth is a fabulous writer, but he pretty much stays within his own life. He's so good - I mean, practically anything I've ever read of his I've really enjoyed. He just has tremendous talent. But I think he should have given himself a break and gone deeper into the society.
I found a great many pieces of punctuation and typography lying around dormant when I came along - and I must say I had a good time using them.
There is no motivation higher than being a good writer.