The Atlanta Hawks trading Luca Doncic for Trey Young was a major mistake as Doncic has become an All-NBA player while Young and De'Andre Hunter have struggled to fit together.
The Boston Celtics trading the 30th pick in the draft for Tristan Thompson was a move that backfired as the Celtics have struggled in the playoffs and Desmond Bane, who was selected with that pick, has performed well with the Grizzlies.
The Brooklyn Nets giving up seven first round picks for James Harden was a costly mistake as the big three experiment failed and the Nets lost valuable draft assets.
The Detroit Pistons trading Tobias Harris and a first round pick for Blake Griffin was a move that set them back as Griffin underperformed and the Pistons ended up waving him.
The Golden State Warriors trading Jordan Poole for Chris Paul was a trade that did not work out as expected, as Paul did not fit well with the team and Poole has shown promise with the Warriors.