Agree, a friend of mine does a million hardware projects, many of which could probably end up as profitable companies. He doesn't care about money though, he just wants to do fun stuff with hardware and avoid people wearing ties and entanglement with authorities.
Unless you are just playing for your own entertainment (not that there is anything wrong with that), having it as a business both provides a measure of success (users and profits) and to the extent that it is successful (that is, profitable) provides resources for its own continuation.
Yes, when it's experimentation on your core idea. But when experimentation is "playing w/ crowdsourcing", "a fully multilingual site" or "an experiment in transparency" then -- until one of them gains traction -- they're more projects than businesses.
