The former world number one said he had an honest conversation with Djokovic before taking up the coaching role between the end of 2013 and 2016.
German tennis great Boris Becker, who previously worked with reigning world number one Novak Djokovic, has not ruled out a return to coaching, the six-times Grand Slam champion said.
During his stint with Becker, Djokovic won six Grand Slam titles. After they parted ways, Becker was named by the German tennis federation as head of men's tennis, a position he holds today.
"I wouldn't rule out the possibility of becoming a coach again," the 52-year-old told Eurosport Germany's Vocal Athletes podcast.
"In the current situation, it's not possible because I'm responsible for the men's Team Germany.
"But nothing is eternal. If there are players who interest me, who allow me to coach so and want to be open with me, then that's something I could definitely consider.
"The problem is that it is very time-consuming. As a coach of Novak Djokovic, I spent 25 to 30 weeks with him. I have a family and I have other professional projects that I need to manage. But I don't want to rule it out completely."
The former world number one said he had an honest conversation with Djokovic before taking up the coaching role between the end of 2013 and 2016.
The discussion took place just after Djokovic had lost the world number one ranking to British player Andy Murray.
"My promise to him was that I had to tell him open and honestly the truth," Becker said, adding he told the Serb, who remains a close friend:
"'The reason why you might not be so good anymore is because you felt too good as number one, you didn't improve. The other players like (Rafael) Nadal and (Roger) Federer have adjusted their game. I don't like your positioning on the court, I don't like your serve at all.'
"We had a long conversation. He had already won many Grand Slam titles and was an absolute superstar, but he wasn't satisfied with himself and he sought for more."