The guy have revolutionized arsenal. They used to be no more than a mid-top table team before him. Playing one of the most boring football around and he transformed them.
People say he didn't win anything for 5-6 years but arsenal used to win the league title once or twice every 20 years before he arrived !!
If the guy was given 50-60 million transfer budget every year to spend and failed to win anything then i'd consider him a choker or whatever people call him nowadays.
Wenger knew the probem in his squad in the last few years was the lack of a decent defesnive mid and a somewhat shaky defense, yet his stubborn ass has not fixed anything.
add to that no major trophy in 7 years (and very likey non in the next 2-3 years too) 7 years is a long time in football.
yet Lippi is seen as a senile, sttuborn coach who is a has been, even though he has won the world cup only 4 years ago.