You could easily have a bigger battery car trying to jump a smaller battery car (keeping the terminology simple) and the small gauge wires of the cheap jumper cables won’t let enough amps through.
Think of electricity as water. It takes a lot of “water” to power a low voltage starter motor. And yes, 12 volts is an extremely low voltage. If your jumper cables are your “straw”, a cheap set is like using one of those puny coffee stirring straws. You’re not going to get much water through that straw.