W3C validating broken code

Hi,

I'm not on the list but wanted to say that I keep using W3C to 
validate my pages and it passes them and later I find out some of the 
pages had broken code and I have to use another validator to find 
them, things such as missing carets in table tags, table tags missing 
altogether, and the # sign missing in body tag for color and link 
colors.  I use Doc type 4.1 transitional on all pages.

Can someone explain why W3C doesn't catch these?

Please respond offlist also to info@loriswebs.com

Lori