Gnarlodious said:
This may be an utterly naive statement, but I believe the problem is that radio stations are OWNED by agenda-driven corporations. In that situation, it doesn't really matter what's profitable programming, because you have commercial support regardless of whether anyone listens. It is almost as if radio is now more valuable as propaganda space rather than profit space. Corporations pump money into non-profit assets all the time, because they fulfill another purpose for them. Once corporations grow to that size, they can squeeze out businesses that require a profit to exist. This is historically the monopoly stage of capitalism.
I can't speak for every company, because I haven't worked for them all. However, there is at least one that busts your "agenda-driven" idea. Cox Radio.
Founded by a 3 time former Democratic Ohio Governor (James M. Cox - who ran unsuccessfully for President with FDR as his running mate), a heavily Democrat family (one of his daughters flew to Dayton, Ohio in 2004 to campaign door-to-door for John Kerry), owner of quite a few newspapers whose editorial boards are notoriously left wing...
Yet, all of their news-talk stations are conservative talkers.
You see, if they were all about "agenda", why wouldn't Cox have been first on the air with liberal talk? But, in my opinion, with them, it's about making money. Which, thus far, most liberal talk stations haven't been able to show great strides at.
Jay Marvin makes some great points about some of the liberal talk shows. (And, Jay: I used to listen on WLS when I worked in Champaign-Urbana.) While I think there's hope for some of them, some of these hosts are, well, beltway pundits turned radio people. That's a problem. And radio is both a science and an art when done correctly.
Way back when (in the days of the Fairness Doctrine), I once worked for a talk station that had a mixture of conservative, liberal even libertarian hosts. They were "equal opportunity offenders". If there wasn't a day when we got complaints about one of the hosts, we checked to see if the transmitter was working properly. But, that having been said, it always seemed as though the liberal host, while popular, had, more often that the other hosts, times when he was ratings-challenged. Don't know why...that's just the way it was.
Lastly: a word about "weak signals". Signal is an issue, no doubt. But, what you have to recall is that the Rush Limbaugh program got its' start on a lot of these same signal-challenged radio stations. I worked for one of those that carried him in the early days, too. Rush clearly became the star of the station. When he moved his show to the big talker in town, his ratings doubled. (The effect of a better signal.) But, when the same station did liberal talk some years later, it got half the numbers Rush did. And the station didn't turn a profit.
I still contend, despite all this, there is a market for liberal talk. But, I continue to believe it's about entertainment, not ideology. If you can talk, not just politics, but issues of the day and make it entertaining, you will get an audience. But if all you do is harp day in and day out the same "Bush is the devil", (Or "Clinton is the devil"), and that's your whole act, you're doomed.