Google is successful and it's page rank algorithm also does not deliver correct results all the times.

There's no such thing as a correct result to a search query. It certainly delivered exactly what was asked for, a grep of the web, sorted by number of incoming links.

They also don't use it at all anymore, they barely even care about your search query.

Google is successful, however, because they innovated once, and got enough money together as a result to buy Doubleclick. Combining their one innovation with the ad company they bought enabled them to buy other companies.