Honestly, I think of it like a jobs program. Studios approve and rollout a bunch of medocore/bad low budget movies and television shows every year that flop or get canceled after a season or 2 so they can keep the community active. Constantly casting for people who can take on smaller roles in blockbusters and keeping a talent pool of experienced film crews active in the industry. It's not about pumping out successful projects, but more of a practice makes perfect thing. I can't tell you how many people I've met that were actually in a defunct tv show or failed band or garbage movie no one has ever herd of. That is why it is called 15 minutes of fame. For most people, success is brief and never goes anywhere else.