"I wish I was a baller, I wish I was taller"
The famous Skee-Lo song says it all. Every basketball player growing up dreams of being tall. All basketball players wish they were taller. Players plead with coaches to list them on the roster a inch or two taller. To be a baller the rule is you must be tall. Obviously, this is not true but most people believe it.
The interesting thing is that the game needs to be played low to the ground. Ball-handling is better the closer the ball is to the ground. Moves are more explosive if you are low to the ground. Post players cannot be pushed around easily if the post player has a low center of gravity. Almost every player could improve their game by constantly being lower to the ground.
Standing straight-up is the opposite of being low and will rarely do any good on the basketball court. The only time where I can think of that standing straight is a good thing is when creating a wall for someone to shoot over in the post area. Most players catch while being straight up and down then have to get lower to make a move or to protect the ball. When every player catches with their knees bent it is a indicator that they are well coached and that they are probably pretty fundamentally sound.
One thing about being low when making a dribble move...you need to actually get even lower on the move. Even if the player's knees are bent, on the move itself, they should get a little bit lower to increase ball protection and to increase the explosiveness of the move. Players usually think they are lower than they actually are. They will also think bending at the waist counts as getting low. Exaggerate the knee bent/squat-like position in practice because we all know in games there will be some slippage.