To further the analogy, if you make your living cooking using a microwave, you better know how one works, how micro-waves propagate, how they interfere with each other (superposition), creating either constructive or deconstructive interference, creating hot and cold pockets, how they are generated and where they come from in a microwave, as well as ideally how heat works… And so on. Otherwise you’re just gonna end up with mushy food that has hot and cold spots, and not know why or how to fix the problem.