when it comes to the draft there are things that can make a player excel in the nba.
Size and length - no matter what you do you can not get taller or longer (except for those few who still grow a little)
Motor - is what they call it and to me that means players that come in and never stop working while on the court. Defense and offense
Work ethic - This is what players do off the court to become better on the court. This is hard to gauge because there are players that seem to put in the effort but dont improve. IE shooting a 1000 3 pointers with a broken shot. This is where Hayward excels as did the mailman. They continued to improve small parts of their games.
Competitive - This to me is huge because it is easy to become complacent with losing. These are the players that want the call in the 4th quarter. These are the players that want to beat the person they guard every game. If you look at Gobert he gets pissed when some one scores. He takes it personal. I will remember when Wiggins dunk on him and then Gobert came back later and stuffed another dunk attempt and gobert stood over him and flexed.
Desire - the is really tough to gauge but you want to be the best you can be. it is taking everyting above and pushing yourself. It is part of everything previously listed.
Basketball IQ - I dont care how much talent you have if you cant think the game of basketball you will never be successful. this is where Ingles has grown immensely.