After just one season at the Camp Nou, Pjanic has joined Turkish giants Besiktas on loan for the rest of the 2021/2022 campaign.
The 31-year-old Bosnia and Herzegovina international joined Barcelona from Juventus in the summer of 2020 but featured mainly as a substitute under the Dutchman.
Pjanic made 30 appearances across all competitions for Barcelona last season but failed to record a single goal or assist.
Asked if he was disrespected at Barcelona, Pjanic told Marca: "The coach, yes.
"I couldn't get used to the situation I faced last year. I knew I didn't want it. I'm a player. I love playing football, this is what makes me happy.
"I always wanted to play for Barca but I didn't expect the situation to get so complicated.
"There was a point that I was playing less, things were getting complicated. And when I played it was difficult physically and mentally to be well, because it was killing my confidence, because I had no communication with [Koeman].
"It was very strange, because a coach is the one who says who plays and who doesn't, but there are different ways to do things. I am a player who can accept everything but I would always like to be told things face to face. Not as if nothing happened and I was 15 years old."