Pioli left Al-Nassr over the summer to take on Fiorentina for a second time his career.
His former agent, Bruno Satin, told Radio FirenzeViola: "I imagine he wanted to return after his experience abroad. Fiorentina and this city are special to Stefano, and I think that's why he wanted to return. I think it's a great opportunity to keep the team at the high level, where (Raffaele) Palladino took them last year.
"Let's see if Fiorentina will be able to compete for the top level after the transfer window. He's the best for a club like Fiorentina. Beyond being an exceptional man, he's also a top coach, and I think it was an opportunity for Fiorentina they couldn't miss. Let's hope they can build a competitive squad capable of fighting for a Champions League spot, which would be the best thing for the Viola."
Satin added: "I think this experience in Saudi Arabia, in particular, helps you grow as a person. You have to be more flexible because it's different from coaching in Serie A, which he knows perfectly.
"He had to develop other qualities, and I think he'll have changed in that sense. With so much experience, he'll also be more relaxed in his approach to matches. I know the demands of the Fiorentina fans who think they can fight to win everything all the time."