@calcifer
I guess depends what it really is, I mean if it's a thing like "could be my week end fun project, here it is, if you like it fine, if you don't fine the same, if you want to use it do it, but it's just a thing left there as it is" that I think is what you call here "Open Source". But SOME "Open Source" is actually/really presented/sold/sometime marketed "as a PRODUCT" well THAT really NEEDS then support, roadmap and fit a purpose. It all depends what you are putting there as "OS".
@gilesgoat @calcifer certainly in my case there are companies that support the software I and others write. But we only provide support to the people and companies that pay for that support. If you just download the product then you are on your own, we'll answer questions on the user list if we have time but we can't promise.