Bob Garfield wrote a column this week about the withering of the Big 4 broadcast networks. He concludes, “The question, therefore, should not be how the Big 4 can cure what ails them. They cannot cure what ails them.” Go read the whole thing, then come back so we can talk about it.

Most of Garfield’s points are absolutely right. As I mentioned awhile back, viewer fragmentation is keeping broadcast TV alive. As viewers scatter, advertisers can still find them in the largest groups watching broadcast channels.

But I disagree that the Big 4 absolutely cannot create breakout hits like Mad Men or Game of Thrones. At its peak, Lost drew over 20 million viewers but Mad Men has trouble reaching 4 million. What does that make, say, The Mentalist with over 14 million viewers? A hit? Mediocre?

The scale and the stakes are different for cable networks than they are for broadcast. The scale is obvious; Fox swiftly cancelled Firefly (4.5 million viewers), but on FX, The Shield ran for seven years (2-3 million).

The different stakes are not so obvious. Broadcast networks need to get acceptable overall ratings to keep their affiliates and advertisers happy. Cable networks need a big hit or two to ensure that customers subscribe to their channels, but the rest of the lineup can be retreads, reruns and filler.

The kicker is that six corporations own all major broadcast and cable networks. So losing a viewer from broadcast to cable doesn’t subtract money from a corporation’s profit, it just shifts it from one pocket to another.

Considering all this, broadcast network programming choices make a lot more sense. Competition and reality shows are cheap to make, and some of them become hits anyway. There’s no need to try to fill the schedule with high-quality scripted programming. If you go too lax and overall ratings suffer enough to rile the affiliates (see: NBC), then bump up the quality and get back in the ratings pack.

In other words, the Big 4 can cure a lot of what ails them. There’s no reason they can’t spend money and take chances to make the next Lost or 24. But it’s a lot safer for the Big 4 to avoid all that. They simply don’t care that much about finding a new cure.