Salary growth, labor productivity, and inflation

I've been wandering this sub for years. What I missed from all these years is a coherent understanding of how all these variables interact with each other. What causes the effects, which are just consequences, and vice versa, what starts the vicious circle. Maybe I'm just stupid, or my understanding of the economy has been reduced to "wages provide people with the means to pay prices. Prices are formed by supply and demand, and supply is the result of wages". The effects should be obvious. But what about the causes? How could this even have started? Businesses need to pay wages to form supply. And if wages are too low, businesses form supply at a loss, which obviously doesn't work. I mean, it's actually even clearer the other way around. Low prices are only possible for businesses that pay low wages. But low prices mean low budgets that can't cover low wages, which in turn mean low prices. The insanity is endless. <br><br>tl;dr. What even starts the effects, and how could this have formed in the first place?