Whether they are discontent players who are just waiting for the season to end or they are perfectly content players who are looking towards the playoffs, there are a smattering of players who are coasting through the regular season.
Players who are discontent are players who seem to have a decline in production and seem to be in situations where they aren't happy. They might be on playoff-bound teams or they might be on losing teams, but they aren't happy, and that lack of happiness is hindering their performance.
Other players are coasting, but understandably so. They are getting older or bear a huge onus for their teams, and as a result, are gliding through the regular season, saving something for the playoffs. In such cases, it's not a flaw in their character that they're on here. Rather, it's an admission of their prudence.