When I’m asked about the “most important” skill needed to shoot better my answer is always “Trigger Control”. With this one movement you can make or break your shot placement. That’s why I practice dry firing so much.
In case you haven’t seen these at your local range, the target below is a cool and quick diagnostic target to test your trigger control.
Are your shots hitting low left? Then you might be jerking the trigger. High right? Then you are anticipating recoil. I always print out a stack of these and keep them with my targets for when I instruct new shooters.