Motta is in his first season in charge of Juventus after leading Bologna to Champions League qualification last season.
Zola told Tuttosport: "I have to be honest: he was very good because his first experience at Genoa wasn't great, but already from those months in which he experienced first-hand what it meant to coach the first team in our championship he learned a lot, proving to be a very intelligent person.
"From there he began a growth path that has never stopped, becoming a great reality for our football and beyond."
On Juve midfielder Kenan Yildiz, Zola also said: "In the wake of (Alessandro) Del Piero? It seems a bit premature to me: Alex was already making the difference as soon as he came on, scoring important goals.
"Yildiz is really growing very well and I like him a lot. But he still has some ground to cover to get to that level."