"Football is down to decision making about human beings. That means the rationality is not always the first criteria to make decisions," Wenger observed.
"Only you (the media) believe that if Mourinho leaves, the club will die. Do you really think I believe that? They have great players - do you think because Mourinho goes [Frank] Lampard becomes average?
"Grant has got some experience. He has a completely different style to Mourinho - but that doesn't mean he is not good.
"He does not say all day 'it is only me'. Everybody thinks because he does not say that, he is bad. That is not right.
"You look at what people do and what they say, does it make sense how they act? I like his style."
Wenger added: "Avram Grant is a guy who has worked before with teams and had success in Israel.
"What you have to accept is that you can work in Finland, Israel and if you have some qualities to handle a team it can work at Chelsea as well.
"It is not only one or two guys who can do it."
Wenger, though, accepted Grant had come into a dream job in terms of the team he inherited.
"It is always the players who get you where you are," the Arsenal manager said. "It is the quality of the players and that is where the managing comes in - to get the right quality of players to work well.
"That team works for a long time together and has big personalities, leaders - [John] Terry, [Michael] Ballack, [Didier] Drogba, Lampard, [Ricardo] Carvalho and [Petr] Cech too - personalities who can withstand the pressure when it is needed."