Facts: everything starting from the Linux kernel to u-boot is usually a mess of code which is continuously full of bugs, the documentation is usually something devs do not produce, and when you find yourself in trouble because source is a complete mess, things completely unclear, and what you get from a git clone behaves like a deranged dog on speed ... well ... do you find reasonable to subscribe yourself to a mailing list asking for a piece of advice?
You sound in a very bad mood, so I think you should let it go before a discussion can be fruitful.

That said, even though you're inflating all this probably because of the above, I agree with that on a general level. But if you don't want to be bothered by that, just write your own software from scratch, or use commercial solutions only.
If, like many others, you're using/exposed to open source because doing without it would either take you way too much time, or cost too much (which in the end is the same), well... you know why you're doing that.
it is not fair 
Yes it is. It's free and open. Drawback is that you're not entitled to expect anything including support.
I don't know if you've released open source software before, but if you have, and it has gotten any kind of traction, how did you feel about being constantly bothered with support you'd have to give away for free? That's just not how things work. As to documentation... yes that's often very lacking in many open source projects. But again, how much documentation do you yourself produce during your developments? Why expect more from others (and for free!) than you'd expect from yourself?
Open source doesn't "suck" any more than gifts do. You may not like what you're given, but you can't complain.
And yes, when designing products, open source is to be used knowing fully well what you're getting into.