The way most of us in the industry earn money by making movies is... we don't make movies, we do the craft/support services that those making movies pay for - scripties, H/MU, DPs, ADs, grips, gaffers, PSMs & boom-ops, drivers, caterers, practical effects, stunts and a few dozen others on-set and affiliated production jobs, and, of course, all of the post crafts - editors, VFX, CGI, graphics, color correction, and all of the audio post disciplines. And lets not forget all of the "business" jobs; attorneys, accountants and the like, plus all of the IT folks. And everyone in marketing. And...
For every director who "makes" a film and earns a profit there are many people who are financially invested and/or creatively invested.
You earn a profit by making a product that the consumer wants to buy.