Footwork has a big impact on a player's shooting percentage. It helps them get their body squared up to the basket, gets momentum moving to the basket, and helps to load the shot. So it is important that shooters are spending the needed time on their footwork, and practicing coming into their shot from multiple spots on the floor. The 3 man 2 ball shooting drill is going to allow the shooter to get a lot of quality repetitions in a short period of time. The player will get to develop the needed muscle memory of coming into their shot the correct way each time.
Along with this being a great shooting drill, it can also be a great drill to do in a practice setting with your team if you have side hoops. It will allow your entire team to work on their shooting at the same time. This will allow you to do skill development; while also being mindful of your overall practice time restraints.