McLeish splashed out £9 million on N'Zogbia last summer and has seen only flashes of the inspirational play which helped to keep the Latics in the Barclays Premier League. But the Villa manager insists N'Zogbia is not unique in taking time to settle at a new club.
He said: "I've been up there many times playing Wigan in the past with my team before and Charles was one of the differences. At the end of last season for Wigan, I thought he was the guy that made the difference. If he can bring that form to us on a really consistent level, then Charles is going to make a name (for himself) at Aston Villa."
McLeish added: "Charles has been slow to settle but you only have to look at other examples up and down the country.
"Why has Andy Carroll been slow to settle at Liverpool. Why has Stewart Downing been slow to settle there? You are talking about two great players.
"It is just one of the mysteries of football. You tend to think when you get an English player, or a player who has been playing in England, that they will hit the ground running. But sometimes they need time to settle in so I don't think it is unique to Charles.
"Charles has shown us some great moments and hopefully there will be a few more from now until the end of the season."
McLeish is hoping striker Gabriel Agbonlahor will also make an impact on his return after missing the last three games with a hamstring injury.
He said: "We are no different to any other team in the country in that, if you are missing your top players, it can be a big miss.
"Gabby is one of the top players at this club and is feared throughout the Premier League. He is always a threat because of his pace and the way he imposes himself on a game. If he imposes himself, every player in the country would be frightened of him."