a kid is studying to be a Samurai/Martial Artist...
his two friends are also studying, but with different masters.
One of them is a slacker who doesn't try hard, but he blames his inexperienced and not famous teacher for his own failings. His friend has the same teacher but works super hard and still gets pretty good over a long period of time.
the third student has a famous teacher. The slacker envies him, thinking he's good because of his teacher, but that is only part of it. The slacker doesn't find out till later that the motivated friend with his same teacher is actually the best of all 3 of them because he tries so hard.
so, the whole story is celebrating taking personal responsibility for your life.