Marksmanship is a perishable skill, I believe that an individual must possess and/or work on three qualities or traits:
1. The INITIATIVE to learn marksmanship fundamentals, whether through professional instruction or on their own accord.
2. The PATIENCE to continue to spend countless hours needed, sending rounds down range and learning their equipment platform (aka kit) and themselves. Understanding marksmanship has two parts accuracy (what your kit is capable of) and consistency (what you are capable of).
3. The DEDICATION to maintain your skills matrix and enhance it and your knowledge.