If you care about the radio station and have a passion for it, continue. If you're only in it to make a buck, then just forget about it. The last thing people want to read is "Sorry, I'm going to be closing this because it didn't get the traction I needed. But this journey gave me a great learning experience, so keep watching this space for my next startup!"

Seven years of dedication and hasn't made a penny.

You can easily find many more examples. It all depends on the circumstances of the person and whether they're in a position financially to dedicate their free time to a project.

At that point, the passion has to become a business because, well, that is where the effort is going to have to go. Maintaining it as a passion project is not longer sustainable and you have to choose.

Let's say you had 10000 followers who each listen for 2 hours per day, how would you make money?

By the way, I still pay for http://www.di.fm and have been listening for many years. I pay them $7 per month. I can stop, but I like their playlists and know that whenever I want to code with good background I can trust their music selection to be productive.

Internet radio is bandwidth intensive, which tends to eat profits. I would work on something else where you are more likely to make money in the near term.

You can always run this as a hobby to recharge your mind while taking a break from coding your other projects.

Out of curiosity, I ran the numbers. 10k users at 96 kbps for two hours a day would consume 315 TB/year.

On AWS, that would cost you $246k/yr, just for the bandwidth. However, if you use a dedicated hosting like 100TB, you can get the cost down quite a bit lower. I think you'd need four of their servers at $215/mo each, which comes to $10k/yr. (Note that a single gigabit port has enough bandwidth to serve nearly all 10k listeners concurrently by itself, so four servers would cover peak usage.)

There will be other costs, of course, such as licensing. The yearly cost is potentially low enough that advertising could cover it. Also, a $5/mo premium account would generate enough revenue to cover another 30-60 free users.

A related thought: Internet radio is an ideal application for peer-to-peer distribution, since even a low-end DSL connection can support several other peers. It can also tolerate dozens of seconds of latency. If each listener is capable of supporting two more listeners on average, you'd be able to run the radio station from your home internet connection without any permanent infrastructure.

You've nailed it here (such an easy trap to fall into).

Every idea with intent of becoming a business has the goal of growing and being sustainable. That's too vague. I would prefer to work on ideas that I care deeply about because those are ideas I enjoy the most and if that is true, there is often a more in-depth goal of where I wish the idea or project to be headed even if I don't necessarily have all the details or answers mapped out.

If you don't have an answer like this in mind, at best my suggestion is to keep thinking until something feels right.