Summary
Despite being an extremely successful college player, Garza slipped to the late second round because of the questions regarding how he might fit in the NBA. He is very limited athletically, so there was doubt that he would be able to score at an efficient rate against NBA defenders. More importantly though, his lack of athleticism could make him unplayable on defense. If he's trying to defend in space, it will almost always result in a blow-by in the NBA. He also will struggle to close out to shooters or react quickly as a help defender.

Garza is a skilled post scorer, and he has the ability to space the floor. If his outside shooting is real, the offense could outweigh the defense for him, particularly during the regular season when he wouldn't be targeted as much. He could have a similar role as late-career Enes Kanter, although more skilled and stretchy rather than a bruiser inside and on the boards.

In his limited minutes in '21-'22, Garza shot decently from three at 33% but has struggled in the paint. When you combine his G-League and NBA games, he's shooting only 31% from three, which casts some doubt on his ability from outside. Overall, he has been productive in the G-League, averaging over 20 points per game and nearly 9 rebounder per game, but his efficiency hasn't been great.
 
Cap Considerations
Garza has a $1.6 million team option for 2022-2023, and if the Pistons decline this option he will be a restricted free agent with a $1.8 million cap hold, $1.9 million Qualifying Offer, and Non-Bird Rights. Using his Non-Bird rights, the Pistons would only be able to offer a starting salary of $1.9 million.

However, if they decline his option it likely means that they would not have interest in re-signing him, as there would be no benefit to doing so versus just picking up the option. Therefore, if they decline his option they most likely will not give him a QO, and thus he would be an unrestricted free agent.

Other teams would then have multiple ways to sign Garza as even teams without cap space could use any of the Non-Taxpayer MLE, Taxpayer MLE, Room MLE, or Bi-Annual Exception to sign him. If he hits free agency, Garza would likely only have offers for the minimum.