@Kerosene @Inginsub @pwm two main problems:

The language has no notion of class or custom data types. You get primitives and tables and thats it. There's a huge cope called metatables that allow you to create class-like structures but they are still fully dynamic and it's very very hard to tell what literally anything is at runtime. This is on top of the fact that lua has basically no debuggers in existence. That is to say, they exist but none of them work correctly.

Performance in lua is a dark art. If you stick to using primitive types, the VM is very very fast. If you try to use classes (you're out of your mind if you don't), the VM is absolutely reckless with memory and the same code involving classes/tables will executive 30 TIMES SLOWER than without them. I have benchmarked this over and over and over again.