One theory of accidents is called the Swiss Cheese Model. It demonstrates what stops planes from crashing. A slab of Swiss cheese has several unevenly distributed holes. If several slabs are stacked together it would be impossible for something to slip through unless the holes line up. If even one slab doesn’t align, the impending catastrophe will meet a layer of resistance.
This is the philosophy that aviation follows as well. So, in case one parameter goes out of control, another one, working properly, will come in to stabilise an aircraft. That is why aviation professionals will say that plane crashes never happen for a single reason only. It usually takes a chain of events neatly piling up for a crash to take place.