Andy Murray's complex persona left former coach Amelie Mauresmo concerned she could not help improve his game further.
Amelie Mauresmo says Andy Murray's on-court persona played a part in the end of their coaching relationship.
The pair announced their split earlier this month after almost two years working together.
Both parties insisted the decision was mutual with Mauresmo wanting to spend more time with her young family rather than travelling the globe with the world number two.
However, Mauresmo has also revealed Murray's attitude on court - which often sees him direct his frustration towards his team - had confused their relationship and left her feeling she could not help the Briton any more.
"Andy is complex. On the court, he can be the opposite of what he is in life," she told L'Equipe.
"It can be confusing. I was there to help, [but] I had the feeling I could not get things done.
"I had the impression we got to the end of what could be done professionally. It was concluded that it would be difficult to continue.
"I reduced my number of weeks of attendance since the last Australian Open and we actually spent little time together.
"It turns out that it was a difficult time for him, I could not help him. But this decision [to end the collaboration] was initiated some time ago."
Murray is yet to name a permanent replacement for Mauresmo as he prepares for the French Open.