His team got 89 points last season. Failed to beat City to the title, sure, but that's still some achievement. And in every other case (including for ETH) people always use progress in the league as the true barometer for team progress. Our cup win last season actually worked against our progression as a club, because it just delayed the inevitable.
I'm not saying he shouldn't be replaced if the team fails to kick on, but he's done a good job with them to this point, and certainly a far, far better job than ETH did with us.