This is, perhaps surprisingly, what I consider the strength of C. It doesn't hide the issues behind some language abstraction, you are in full control of what the machine does. The bug is right there in front of you if you are able to spot it (given it's not hiding away in some 3rd party library of course) which of course takes many years of practice but once you have your own best practices nailed down this doesn't happen as often as you might expect.

Also, code doesn't need to be bulletproof. When you design your program you also design a scope saying this program will only work given these conditions. Programs that misbehaves outside of your scope is actually totally fine.