You have combat-focused arts and sport-focused arts. Both of these present various advantages over each other.
Most traditional arts fit into the combat-focus. The goal isn't to win a tournament, it's to protect yourself. There's also newer arts that fit into this as well, such as Krav Maga. These arts teach you how to deal with likely attacks you're going to come up against, in such a way that you're going to be prepared for different environments.
Most modern arts (and a few older ones) fit into the sport focus. The MMA arts (boxing, kickboxing, muay thai, wrestling, BJJ, judo, etc) all fit into the sport focus. The goal is to go into the ring and win a belt. You also learn some good skills to use in the real world.
Now, both of these have their pros and cons. Anyone who tells you one style works and the other doesn't is wrong. Both styles have proven effective in self-defense. But you do have to be honest with yourself and recognize the pros and cons of each style.
Combat-focused arts tend not to spar as much or pressure-test as much. At the extreme end, they say things "our stuff is too deadly for the streets", and while sometimes that's cringe, you also don't want to poke your friends in the eye or have someone repeatedly kick you in the balls.
However, sport-focused arts tend to forget about situations that might be different from they ring. They discount those eye gouges and groin shots. They excuse themselves out of training for weapon defense or 2-on-1 situations by saying it's impossible to pressure test, and you're just gonna lose anyway. Of course, when you ask if they'd just give up or fight back, they say they'd fight back... Most sport arts won't ever talk about de-escalation or what you should do if you encounter a threat. They won't talk about things like how to use improvised weapons.
This is where cross-training (or at the very least, introspection) comes into play. Recognize where your training is deficient, and then do one of two things:
- Accept that limitation, that you don't think it's worth training to overcome
- Fix that limitation with cross-training or specialized drills
Let's go back to what I said about weapon defense. Let's say someone points out that you don't do knife defense in your school. You can look at it and say "that's true, but my primary goal is to win my next match, I'm not going to worry about that right now." Or you can say, "that's true, maybe I'll take a seminar in knife defense, or next time I'm rolling with my friends, we'll use a rubber knife and see if we can use our techniques."
These are both valid responses. You recognize the risk and either accept it or mitigate it. Bad responses are "I'll just use what I know against the knife" (you don't know if your training will put you in danger, i.e. clinching and then getting shanked repeatedly), or "if you train knife defense, you're an idiot."
