5. Klay Thompson
The Dallas Mavericks are a team that is never afraid to make a big swing, but they are also not afraid to admit they messed up and move on.
Last offseason, the Mavs made a big sign-and-trade for Grant Williams, but this deal quickly failed. Williams wasn't ready for the role that Dallas assigned him, and he wasn't the best fit on or off the floor.
There were rumblings that Williams wore out his welcome with the Mavs due to his "yapping" and rubbing people the wrong way, and the Mavs got rid of him in a trade for P.J. Washington in the middle of the season.
Something like this happening for Klay Thompson seems far less unlikely, but there are undeniably question marks with his potential fit in Dallas. If Thompson's defense isn't good enough, the Mavs could have a big problem on their hands.
Dallas already has two players in their starting lineup (Luka Doncic and Kyrie Irving) who aren't the best defenders, and if Thompson can't be a good stopper on the wing, the Mavs defense would take a big step back from what it was last season.
Dallas' defense thrived due to Derrick Jones Jr.'s point-of-attack defense on the wing, and Thompson will at least need to be above average on this end.
All signs are pointing to Thompson being an outstanding fit and he can't wait to get to work and pursue his fifth ring, but things can change quickly in the NBA. Fans should be ecstatic about Thompson's potential with the Mavs, but if things were somehow to go south (which seems unlikely), then don't rule out Dallas moving on.