Usually when a player only spends a few months or a year with a team, something negative was associated with their tenure. The Boston Celtics just saw that a toxic work environment could force several players out of town. Underperforming could result in having your bags packed for you by the front office.
Sometimes, players just have a nice short-term fling though. Maybe they spend a season enjoying the New York club scene and then take a bigger paycheck to play in Minnesota. We just saw DeMarcus Cousins spend a season rehabbing on a cheap deal with the two-time defending champions before taking even less to be playing in Hollywood.