Charlie, very respectfully, this conversation has devolved into me trying to shoot straight and tell you the honest truth, and you not budging until I say what you want to hear.

Anything is "possible". But the statistical chance of a scenario such as you suggest happening is a virtual impossibility. If you want to die on the hill of "technically it's possible" then fine, yes it's technically possible. But again, a virtual impossibility.

Let me walk you through what you are suggesting as a being possible. Part of the problem begins with an incorrect assumption that is often made - that being, that a great song will eventually rise to the top. That's false - it's false because the music business isn't about "art" or "great songs", it's about hits and making money - money THEY make, not money they have to pay you. Assuming a given unproven writer somehow manages to write an epic song, you have to get someone to listen to it. That has become next to impossible because of how out of hand infringement litigation has gotten. If by some miracle you can circumvent that first roadblock, then the exact artist/producer or tv/film music director has to A) hear it, and B) "hear" it (meaning knowing that it's a great song). After that, they have to be comfortable that this unknown writer is not some whacko or highly-litigious individual that would make dealing with them a nightmare, which they are EXTREMELY paranoid about. Get past that, and it becomes a matter of finding the right fit for the song....right artist, right movie, right project; that doesn't happen like turning on a light switch. Then, the song has to be so incredibly stellar, that whichever artist/movie/etc. in question is willing to forego including a song that they wrote or they own the publishing on, and thus pass up on making that money for themselves. After that, record labels/publishers will see that the song is independently published, and they'll come after a share of it, and I mean hard. They'll also be pressing equally hard on the artist/producer/movie guy to include one of their songs, up to and including a "Let'$ do lunc$h and di$cu$$ the$e song$ we'd like you to con$ider". In the ridiculously unlikely scenario that the song gets through all those obstacles, it then has to be selected, out of all the other available material on the project in question, to be THE song - where yet again, songs that were written/published by the artist/producer/etc. are going to be given heavily weighted consideration over any outside songs. Then it has to be a hit - not just a "hit"; but a massive, stay 5 or 6 weeks at number 1 and spend months on the charts hit, which is yet another needle in a haystack.

On top of all that, the writer in question would have to be so incredibly frugal, so grounded, so financial mature in their thinking, that they wouldn't touch any of the royalties when they came in, other to invest them. That's a hell of a lot harder to do than it sounds. I've gotten some of those 5/6 figure checks that you're talking about. The discipline it takes to not spend any of that money, even "just a little", is almost superhuman. The lottery comparison you made is an interesting one - go research how many lottery winners have wound up bankrupt after winning - the number is a lot higher than you might think.

This question has had me intrigued, so I put out a bunch of phone calls out to peers of mine, writers who have written hits that were #1 songs (plural, more than one). None of them, not a single one - believes that a writer could retire off of one hit. And in the going-on 40 years I've been in Nashville, I've never met a writer, or heard of any, who did.
I've been giving the Nashville perspective (obviously), but as daunting as I make it sound, it's far far easier to make it here than in NY or LA.

Yes, anything is possible. I could win powerball tomorrow - it's possible. Expecting that to happen, or even hoping for it, isn't much of a retirement plan.

http://www.rogerbrownsongs.com
http://www.nashvillesongwriters.com/roger-brown