The attacker, who joined the London outfit from Lille in 2011, departed for Roma this summer after falling out of favour at the Emirates Stadium.
"I was not getting much time on the pitch and was in need of this time to improve and play my best football," he told The Sun. "Wenger was not prepared to give it to me.
"Also my position on the wing was not what I was expecting and I wasn't happy with it. It would have helped had he shown more confidence in me."
Gervinho made 45 league appearances during his two seasons in England.