The 24-year-old joined Chelsea from Bayer Leverkusen ahead of the 2013-14 campaign, but failed to secure regular first-team action at Stamford Bridge.
The forward therefore opted to leave Mourinho's side this January despite receiving assurances from the Portuguese coach that he would feature on a more regular basis.
"I have been a Chelsea fan ever since I was a kid and I felt well there right until the last day. But the most important thing for me is playing football and enjoying myself. This was no longer the case," Schurrle told Sport Bild.
"Wolfsburg might be a smaller club when you look at reputations and I thought about it long and hard. I could have stayed at Chelsea. Mourinho told me that I would get my chance.
"You have to make a decision, though, and in the end I only wanted to play football again. Germany coach Joachim Low told me it would be a great move for me and that is why Wolfsburg are a step forward for me.
"Wolfsburg have a great team as well and can play for silverware in the Bundesliga and in Europe."
Schurrle has made two Bundesliga appearances for Wolfsburg so far, creating one goal.