Things change quickly in the NBA. Less than a year ago, Luka Doncic was leading the Dallas Mavericks to the Western Conference Finals, but on Friday, Doncic played only a quarter as the Mavericks completed their historic two-month collapse from No. 4 seed to the lottery. Dallas went 9-17 after acquiring Kyrie Irving from the Brooklyn Nets, sacrificing their defense and depth in the process, and their franchise player is reportedly starting to get impatient. In fairness, he already had been. Doncic reportedly asked the Mavericks to get him help during the season. That led to the Irving trade. But…