But the actual answer here is probably a combo of a few things: One, running a company is probably not as much fun as building a company. Much of my career has been "pioneer" roles where nobody else has done the job before. At a certain point, the foundation is laid and the problems to solve are different and often less interesting -- at least to me. It's the build vs. maintain thing.
Two, they started with good and noble intentions. Money got involved. A lot of money got involved. The noble intentions were replaced with reality.
Three, have you met users? As a site grows you have to deal with more and more people and people can be very demanding and not very appreciative. Coupled with the previous factors, I think original founders get burnt out and decide to take the cash and move on. The allure of building anew is too much, the grind of maintenance is too much, and the cash is too good to pass up.
Also four... there's a peak for any site. You often don't know when or how, but you do now that someday your site's maximum value, interest, participation, and all that is going to peak and then decline. Sticking around to fight the good fight may just mean passing up a payday and being left with a declining property nobody wants anymore.
Maybe in some businesses pioneering is less likely (by nature, or the corporate culture) like Stack Overflow making inroads into crypto or VR or AI.
And then one day, completely unexpectedly (to me) I read that they’ve been acquired by a private equity firm. I reached out to find out what happened and what changed. His answer was along the lines of “turns out everyone has an exit point after all. Priorities and motivations change and I’ve given this company everything I have to give it. It’s time to explore what’s next”
I think about it a lot. And I’ve witnessed it in various ways numerous time since. People that were hacking on a side project with the idea of “I just want this to be a fun passive income stream” seeing the adoption and love their work gets suddenly thinking “oh my, there’s potential here I didn’t see before! I could build a whole team and company around this… let’s go raise investment!”.
I think we’re just really bad predictors at how achieving the things we want will impact us emotionally. When we reach those milestones we react either more positive or more negatively than we could understand previously.
Keeping control is a (mostly time) commitment and liability. You have to stay on top of things and actively decide on issues that inadvertently come up.
That is assuming the worst in people. Have you ever wanted to move onto something new? If you make something cool, it is not your lifelong obligation to oversee it.
Joel left in 2019 https://twitter.com/spolsky/status/1111267189133316097
Jeff left in 2012 https://blog.codinghorror.com/farewell-stack-exchange/
I'm not sure that it is fair to say that the original founders sold it for that amount.
To that end, with their various rounds of funding ( https://www.crunchbase.com/organization/stack-overflow/compa... ), they likely had very little say in any of it after that series E ( https://stackoverflow.co/company/press/archive/series-e ) which is after Jeff and Joel had left and likely diluted any value they had substantially.
In the case of Stack Overflow, I think the reason for the data dumps was two-fold: one of the original founders (who left long ago) came across as at least idealistic and wanting to do the right thing. The other was pragmatic and most likely always thinking about the money angle. However, the other founder likely also saw the value of the data dumps from a PR standpoint which was quite valuable as they were initially trying to replace expertsexchange.com that paywalled most of the content. IIRC, they discussed the data dumps in the early days of their podcast.
Now that there's big money to be made from machine learning (both the models and the data they are trained on), they've likely decided 'screw it' on the PR value of the data dumps and would rather get some of that sweet, sweet machine learning money.
Experts Exchange was well known for showing up in search results but not providing the answers without paying. Many people hated it and wanted search engines to implement some sort of deny list to filter it out automatically.
They typically have millions of reasons. Sometimes billions.