Fundraising for open source has become trivial through venues like Kickstarter, so it's natural more projects are asking for money. "Imagine all the good I could do if I was able to work on this full time for the benefit of the community". Yes, let's imagine indeed.

First of all, it's tempting to cash in on goodwill earned. Prolific open sourcerers rightfully earn the gratitude and admiration of their community. But given the questionable success rate of putting out your hand and asking for money (in terms of the project, not the money), means that it's like a one-time deal. It's a cliché, but once you've sold out, the goodwill might well be spent for good.

Second, part of the reason much of open source is so good, and often so superior to closed-source commercial projects, is the natural boundary of constraints. If you are not being paid or otherwise compensated directly for your work, you're less likely to needlessly embellish it. You're solving the problems for you and your mates, likely in the simplest way you could, so you can get back to whatever you originally intended to do before starting to shave the yak.

But once there is money involved, work will expand to fill the amount raised (to paraphrase Parkinson's law). A $50,000 project will magically match $50,000s worth of effort. Regardless of whether an early insight lead you to discover a way to let it be done for a tenth of that. It puts you on a more rigid production plan, which isn't likely to benefit from simplifications. It's a waterfall process.

This problem is even true from the outset. If you're asking to derive your daily bread from open source work through community donations, you'll work to ensure the stability of that bread — inspiration or not. This often doesn't gel well with the wax and wane of creative insights. There is something lost when you share because you must, rather than because you can. It's also what leads to consultant-ware (software that's needlessly complex, and requires you to buy consultants to figure it out).

But the most important issue I want to address is what happens when you change from social gratitude to market expectations in reaction to your work. (Predictably Irrational has a great chapter on this.)

External, expected rewards diminish the intrinsic motivation of the fundraising open-source contributor. It risks transporting a community of peers into a transactional terminal. And that buyer-seller frame detracts from the magic that is peer-collaborators.

It also holds the threat of corrupting the community at large. We plant the seeds of discontent by selective monetary rewards. If project A gets funded, it implicitly signals increased comparative worth over project B. Now the makers of project B might well grow dissatisfied with their lack of compensation, and their intrinsic motivation too take a hit. (See Punished by Rewards for more on this).

It's easy to discount such discontent as silly. Why should the makers of project B care what happens in project A? How is their lot any worse because what others choose to do. That's the intellectually superficial response.

But human nature is not so easily dismissed. We all hold an innate sense of justice, and that sense is disturbed when others take extra reward for similar work. Arguing against the rationality of that is to argue against human nature.

Open source has been such an incredible force for quality and community exactly because it's not been defined in market terms. In market terms, most open source projects should never have had a chance.

Take Ruby on Rails. More than 3,000 people have committed man-decades, maybe even man-centuries, of work for free. Buying all that effort at market rates would have been hundreds of millions of dollars. Who would have been able to afford funding that?

That's a monumental achievement of humanity! Thousands, collaborating for a decade, to produce an astoundingly accomplished framework and ecosystem available to anyone at the cost of zero. Take a second to ponder the magnitude of that success. Not just for Rails, of course, but for many other, and larger, open source projects out there with an even longer lineage and success.

It's against this fantastic success of social norms that we should be extraordinary careful before we let market norms corrupt the ecosystem. Like a coral reef, it's more sensitive than you think, and it's how to underestimate the beauty that's unwittingly at stake. Please tread with care.