Apparently, it was two main factors that led to Lamar being permanently benched.
An insider very close to Dallas Mavericks owner, Mark Cuban, said:
"The decision was made by the team owner Mark Cuban after Lamar did not play in the second half of a game against Memphis.
The team was upset by his inconsistent effort on the court and was concerned about how his demeanor could impact the team's younger players."
So even though Lamar said:
"The Mavericks and I have mutually agreed that it's in the best interest of both parties for me to step away from the team."
…it was another insider that said it was "too much drama, [and] not enough focus on basketball" that led to his departure.
[Image via Robert Wallace/WENN.]