There's a reason the BBC often has a lot of good stuff. They give some talented nobodies some money, tell them to make a show, with no expectation it'll be a big hit. Sometimes it turns out to be a cult classic like Hitchhikers Guide to the Galaxy, often the talented nobodies learn the ropes and their next show ends up being great.
Nurturing talent isn't profitable, but you do it anyway because at least some of that talent will make you money a few years down the line.
Bit of a tangent, but go on the BBC sounds website. You'll find loads of (science fiction) dramas from authors and actors you've never heard of. I suspect the amount of people who've actually ever listened to some of them is miniscule, bu itt's a cheap way for the BBC to give new talent an opportunity to write and act in something, to develop their skills.