As evidenced by the Cleveland Cavaliers storming back from a 3-1 deficit in the 2016 NBA Finals to win the championship, LeBron James is a master motivator and is the true epitome of a leader. They don't call him King James for nothing, so when he makes a decree, people usually listen.
This also apparently applies to James' non-basketball friends because according to TMZ, Justin Bieber reportedly turned down $5 million dollars to perform at the Republican National Convention because the Cavs superstar advised against it.
From TMZ:
Justin Bieber got a $5 million offer to perform at a Republican event during the GOP Convention, but turned it down after his manager considered quitting and LeBron James urged him to reject it ... sources tell TMZ.
James may be a bit salty at the RNC because they nearly took down his iconic Nike banner in downtown Cleveland for the event. However, James also knows plenty of about building one's brand and likely doesn't want to see a friend like Bieber, do anything to further harm his not-so-stellar reputation.