This is a very interesting article,

Can You Train A Great Penetration Tester?

The hacker mindset can't be taught -- it must be developed and refined over time

According to the author, there are different types of penetration testers:

• Novice level. They know the fundamentals of security, the attack methodology, and the testing techniques. There is marginal skill improvement with additional experience.
• Advanced level. This requires study, especially, self-study. Focused and continuous learning is essential in being effective as a pen tester. It requires passion, learning and training.
• Expert level. It can not be trained. They possess "hacker mindset", which can not be taught. It must be developed and refined over the years. Two key talents: the ability to synthesize disparate data to create actionable information and the knack for identifying and pursuing the most effective attack path against a target.
• Master levels. They have one secret that sets them apart from everyone else....