Depending on the organization, individual school, and chief instructor within a school, a formal apprentice training program may be non existent or it may be long, detailed, and arduous. In traditional schools, the apprentice is first treated as a virtual slave (doing medial labor while learning little), gradually gaining more freedom, benefits, and training until the final certification. As stated above, this process is still used by many other professions, such as the armed forces.
In the U.S. Navy enlisted ranks, chief, senior chief, and master chief petty officers are not only the top enlisted ranks; they are the ones who run the day-to-day operations of the Navy. There is little to no formal training on how to achieve the rank of chief, it must be absorbed through years of watching chiefs and learning from them—the apprentice training system at work. After making chief, there is a training course on how to be a proper chief, but there are no training courses for potential chiefs to show them how to become chiefs. If you emulate the wrong chief, you may not become a chief and, even if you do become a chief, you will probably be a poor one and will then pass your poor behavior on to other potential chiefs. I had many sailors complain about my being to tough on them. I had many sailors thank me for being tough on them. However, I never had any sailor thank me for being easy on them
The problem with any apprentice system in Taekwondo is that the apprentice emulates the master. This means that the apprentice emulates the master’s good attributes, as well as the bad ones, and then passes the good, and bad, aspects to other students. The apprentice’s learning is limited to that which the master knows and is able to teach. A master may be proficient at performing Taekwondo and may be proficient at teaching Taekwondo, but does not mean the master is also proficient at teaching others to become teachers. These are separate skills. A master is known for the quality of students he or she produces, but a great master is known for the quality of the instructors he or she produces for they will affect the quality of Taekwondo long after the master is gone.