Straight from Google: What You Need to Know
mattcutts.com
mattcutts.com
For example, if I have a web app that converts numbers between bases (just an example, OK?), Google would ignore me, since my home page is just a couple of text fields and a submit button. (If it's ajax, I don't even have a submit button)
So, I say, "OK, fine, Google, you want text, I'll give you text", and I add a blog, saying some stuff about converting numbers between bases. That works a bit, but really, I don't have that much to say about converting numbers between bases. I have this app, it works well, what's to say? So, I rapidly run out of things to say in this blog I was forced to write. Google sees my site as never having new content, and down I go.
Of course, if I had a bunch of incoming links, no worries, but I won't get them if nobody can find me in the first place.
Try searching for 'anything review' and you'll get 99.99% spam. Made it very difficult for me to make an informed choice about buying a new monitor recently.
I don't understand why the big G doesn't immediately ban all spam sites. They take about 0.1 seconds to identify by a human viewer.
Obviously not suggesting that G curates the whole web - but jeez purging the worst offenders would make life easier.
I wish it weren't true, because apart from it being the biggest thing spoiling my admiration of Google, the prevalence of such garbage sites is the biggest thing spoiling the usefulness of the web.