>For the very few, the answer is: when someone wants or offers to buy your company.

It seems that way from the perspective of having never received an offer, but my own experience makes me skeptical. I haven't been in that specific position, but I have had a possibly analogous experience.

For a few years, I developed and supported myself with a graphics-tablet targeted shareware drawing program (now sadly, due to changes in the Mac shareware ecosystem, one of my backburner projects). One of the "big breaks" I imagined might come my way would be if a tablet vendor wanted to bundle my software with their hardware.

And one day, toward the end, I got an offer for exactly such a deal. A small vendor wanted to include my program in a tablet bundle for a relatively small holiday run. They wanted to know what I would charge per-license. I did some research to find out what a typical OEM markdown would be and made them an offer based on what I found. It was a significant discount, but it was a fair price, and I'd have made reasonable money off of it. They responded saying that this was far too much and that they really couldn't go over $1 per license, which would have been more than a 95% markdown. I attempted to negotiate further with them, but they stopped responding to my emails shortly thereafter.

Should I have just taken them up on their initial offer? Well, as the cards finally fell, I would have probably made more money that way. And if I'd known that I would shortly be shifting my focus away from development of that program, I might have made a different choice. But whether or not I made the right choice given the information available to me is not the point. The point is that it wasn't an easy "yes".

When you aren't getting any offers, it seems like any offer would be a coup. But that's not how the market works. If your company is worth $5000, there's somebody out there who would be happy to pay you $200 for it. You won't see many offers like that because the number of businesses worth $5000 is large and the number of people who are willing to send out insulting offers is relatively small. But "say yes to every offer" isn't a winning strategy.

If they didn't write back, it's hard to imagine they were serious about the offer. How likely is it they were just testing the waters with various providers?

It's also very likely that they weren't very competent. If I recall correctly, they wanted this for a Christmas sale, and they contacted me about it in late November.

Agreed, most often selling a company happens out of necessity rather than choice and founders are looking for buyers rather than just weighing the pros and cons of unsolicited offers.