Shooting practice is needed and to become an advanced sharp shooter you will need hours of practice. However, much if not all of your practice is against single and stationary targets. The targets do not move, sneak up behind you or climb buildings to fire down upon you, in practice sessions anyways. Anyone that has confronted a shooter when there is no advanced warning or it was not a planned attack on your part has to wonder if the shooter is alone. Do you focus on the one you can see or should you look for others. What happens when there are multiple shooters/attackers?
This interview is a must read for any shooter or person interested in self defense. I have learned so many useful things from Peyton Quinn from Rocky Mountain Combat Applications Training.
Interview with Massad Ayoob, top firearms and self-defense instructor.