Why google answers was retired?

I have checked and it seems that Google retired its service similar to www.ehelp.com - what is the reason if you have an idea?

Google is about advertising. EHelp is about help. We have a dedicated group of people that understand the secret of success: What you get out of anything is based on what you contribute, not what you want. Try it; it really works.

Google's official answer to registered users was:
"We considered many factors in reaching this difficult decision, and ultimately decided that the Answers community's limited size and other product considerations made it more effective for us to focus our efforts on other ways to help our users find information."
http://www.metafilter.com/56634/Google-loses-one-battle-to-the-competition

... and do what Rob says. lol