Everyone connected with the NBA watches games when they can, and the reasons are myriad.
Players watch to see what their buddies are doing or what their old teams are looking like, or because it’s a particularly compelling matchup. In many ways it is mindless entertainment, and because they get so immersed in a season as it goes on, watching becomes the normal off-night lifestyle.
Coaches tend to watch with a more discerning eye. They look for plays and player rotations and out-of-timeout or end-of-game situations they can tuck away to either steal for their own use or be prepared to defend if a similar situation arises.