Paraphrasing Peter Norvig: ".. if you do experiments and you're not failing half of the time, then you aren't getting enough information out of those experiment

Paraphrasing Peter Norvig: ".. if you do experiments and you're not failing half of the time, then you aren't getting enough information out of those experiments." (from http://www.slate.com/blogs/thewrongstuff/2010/08/03/error_message_google_research_director_peter_norvig_on_being_wrong.html http://www.slate.com/blogs/thewrongstuff/2010/08/03/error_me... ) ;-)