When teaching kids, you have to look for “talent”
But I think the MOST important element that can help a kid get some success with tennis at a young age is their competitiveness. If there is a kid who is “competitive” in that they really want to win the matches, then they will be willing to fight and “grind” in order to win points and win games and ultimately win matches. They will grunt and bend their knees and exert their force in order to try and win.
I have definitely seen kids who are in tournaments but they really don’t care at all. Or they don’t try their best. They could be rich kids or their parents want them to play. But they really don’t care if they win the matches, they are not going to fight for it. In theory, wealthy kids can eventually do well because they can get so many lessons that they learn how to hit hard and clean balls. BUT, in the end, the advantage goes to the FIGHTER who is willing to battle and win the points. You just have to look at someone like Nadal or somebody like DAVID FERRER and you can see.
That is just my 2 cents on the matter.
Look for kids who are very competitive because they will become really good tennis players with the right training and the right encouragement.
-DJ ROBO BISCUIT