Team building is really difficult in professional sports. Drafting, signing, and trading for the right players is one thing. Then there is putting a good infrastructure of coaches and management to develop and maximize them.
Doing all of these things correctly doesn’t guarantee success — injuries or plain bad luck can undercut even the best laid plans. The teams most capable of adapting to these circumstances are able to overcome these obstacles.
For example, take the early 2010’s Portland Trail Blazers, who had both Greg Oden and Brandon Roy’s careers cut short due to devastating injuries.