Effort, hard work, feel for the game, clutch genes.. I think you need to take these into consideration too. Granted Oubre is still young but I don't see a lot of 'fight' in him. There is plenty of 'fight' in Dekker.
If you watched Aaron Harrison in the tournament last year, you would have said he had clutch genes too... Don't overreact to one or two games. Dekker is a 34% 3-pt shooter and an average defender and rebounder at best. He's not a starter in the nba, imo.