Tarık Biberovic didn't go to the NBA. He signed a new three-year contract with Fenerbahçe.
He may not have earned the money he wanted in the NBA.
Tarık showed great development at Fenerbahçe, where he joined at a very young age.
He was 17 when he joined Fenerbahçe.
The details of his contract and his salary were not disclosed, but I believe he received a good salary.
To be fair, he doesn't really have the stats in the Euroleague that would warrant a move to the NBA, especially when he is "already" 24 years old, so there is not much development to be expected. Scoring around 11 points per game and only 2.5 rebs and 1.5 assists per game doesn't really fill up the stat sheet, that's what NBA teams are looking for though.
It's as you said. Although Biberovic is a good player, he doesn't have the package that NBA teams want/demand. However, I don't believe that a player at his 24 years is done in terms of evolving and becoming better as years pass. He needs to work hard and play as much as possible, and while he can find this in Fener, the NBA will not give him the time or the space that he needs for this. It's a good move both for him and Fener, and I'm sure that his numbers will be better year by year.