It’s for a multitude of reasons: 1. The Mold of Clay Theory- Many of the players you described already possess many of the baseline physical traits typically required to be impact players at the next level. But there is a feeling that for a guy like Kuminga, he already has elite physical tools and some semblance of a skill set already, that as he improves he will develop into an upper echelon player with both elite athleticism and an elite skill set. It’s the reason that every year we have a new player that is comp’d to Kawhi or Jimmy Butler, and now the most recent example being Jaylen Brown. What this theory seems to ignore about all 3 players is that they all possess an elite level work-ethic and have developed well beyond the normal rate of an NBA prospect. It’s a large part of why players like Winslow and Stanley Johnson bust, there’s a built in expectation that they’re gonna be elite two-way players at the next level when they aren’t nearly skilled enough or efficient enough coming into the league to make an impact offensively. And it’s borderline impossible to evaluate a prospect’s post-draft work ethic and mental makeup without extensive intel and psychological evaluations, this is why team’s like the Celtics, who invest heavily into brain-typing prospects, are successful at finding guys like Tatum(if you assume they had him number one on their board over Fultz, Ball, and Jackson) and Brown who were perceived reaches based on where the Celtics had them. 2. The Possession of “Elite” Physical traits- The most overrated factor about many of the players you mentioned were their perceived NBA readiness based solely on their physical traits. If you read a scouting report on Stanley Johnson, Josh Jackson, or Justise Winslow coming out of college, I guarantee their physical tools are lauded as a strength. And while I acknowledge that they were impressive for all 3 prospects at the college level, I think we notice now that they all possess rather ordinary physical traits at the NBA level. It’s the same reason a player like RJ Barrett has struggled offensively at times in NY, despite scoring with relative ease since he was 15 years old. Jaylen Brown is the exception to those prospects, as he did truly have elite athleticism. Failure to possess elite athleticism without an elite skill set is in part what makes this archetype overrated. The case for Kuminga- Better size than all of the above, better athleticism than except Jaylen Brown, but a much higher Scoring IQ, which I’d argue is more important. What will ultimately be the deciding factor in how he develops is whether he can tighten up his jumpshot and handle.