Also, keep in mind that it can take a while for the site data to show up in Google Webmaster Tools. If you have only recently registered the site with GWT, you might need to wait a week or two.
I don’t think that’s true. Virutally all sites get indexed, regardless of quality. The only significant exceptions are sites that violate the law in some way, or are deemed offensive or anti-social - and then often only extreme cases.
It’s true that Google take quality into account when ranking a site. In general, a site that Google deems to be of high quality will outrank a lower-quality site - all other things being equal. But that’s a far cry from saying the low-quality site won’t be indexed at all.