My bad, I guess everyone makes mistakes in their own lingo.
Yes, he's a very good player, but he has not matched the expectation we have of him here in Great Britain, therefore he is a failure.
The only reason why he hasn't reached the expectations of certain individuals in Britain is because of the expectations he has indirectly set himself, by winning some of the biggest tournaments and beating some of the best players in them. He has exceeded realistic expectations that were set by reasonable analysts back in 2005.
He is far from a failure, he has done incredibly well. Regardless of whether he wins a slam or not, he's had a career anyone who's starting out would dream of.
And this is coming from someone who detests him, I'm just not that unreasonable.