Several players for the Boston Celtics reportedly had issues with Brad Stevens' approach as head coach. Per Jared Weiss of The Athletic, the dynamic between Stevens and Kemba Walker was "tension-filled," and at some point they did "butt heads, though the pair were considered to have a productive working relationship and mutual respect for one another."
The knee issues that plagued Kemba Walker since the second half of the 2019-20 season played a role in the Boston Celtics' decision to trade the four-time All-Star. ESPN's Adrian Wojnarowski reported on NBA Countdown that the Celtics had "such concerns" about Walker's knee and "how much he would really be available for them and able to play at a really high level" over the next two seasons (starts at :39 mark). The Celtics announced on Friday they had traded Walker, the No.
Those three men are on a lot the lists of a lot of teams.