Lehmann doubts whether Arteta has what is needed for the Gunners to take the final step.
"Arteta has done really well bringing Arsenal up, but if he is the right man for Arsenal now… I am not sure," Lehmann told the Telegraph.
"Because you need to prove it. We could have won (the league) twice. Last year, they were leading, and in one month (April), they lost it (three draws and one defeat).
"The culmination was when (Bukayo) Saka missed the penalty against West Ham at 2-0 up and it was a draw. It was two points.
"What people who hire coaches sometimes don't understand is that the personality of the coach is super important as well.
"Look at the personality of the coach. Is he a winner, or is he a nice guy who brings you to a certain level and then it is over?"