A Marine is a best-practice warrior who models the highest levels of what military training can accomplish.
The Marines are by no means the only people who take such transformative experiences seriously. Colleges and seminaries talk a lot about this process, each claiming that it turns out world class leaders. There are businesses (Starbucks comes to mind) that believe that their profitability depends on turning employees into best-practice sales representatives.
How about churches and their goal of making of devoted followers of Jesus? What does the difference look like there?