I'd argue that's what makes the art so rich. There are so many different ways of doing things, and different Masters have picked what fits their game and designs the best.
You see this as a weakness, but I see it as a strength. Because someone can go to the piercing school and learn a piercing kick from someone who is truly an expert in that kick, to the thrusting school and learn the thrusting kick from someone who is truly an expert in that, and so on.
And then the piercing kick guy can bring in the thrusting kick guy for a seminar, and that will further enrich his students.
This is what I've experienced in my BJJ training. My professor is a world champion. He loves to pull guard and play from the bottom, so the school mostly focuses on how to survive and win on the bottom. One of the brown belts has a very strong wrestling background. When he teaches, we learn a lot more about take-downs and how to win from on top. Another brown belt is short (like me) and so he has a lot of insights that the taller coaches don't. For example, some techniques with your legs simply don't work if you can't wrap your legs around your opponent, but there are variations you can make that the taller folks aren't as familiar with.
If everyone did things to my Professor's standard, I'd be stuck playing a tall man's game. Thanks to the other coaches, I'm able to learn a much more well-rounded skillset.