This is a Georgian idiomatic expression. It conveys the idea that, as a quail will never perch in a tree because it can not, so a person will not be able to accomplish a task or perform, due to his/her inability. Under the word inability, I mean both - mental and physical ineptitude. Is there an equivalent expression with the similar meaning in English ?
To novelist Robert Heinlein is attributed "Never attempt to teach a pig to sing; it wastes your time and annoys the pig."
We can't all play first violin in the orchestra, [somebody has to push wind through the trombone.]
I'm quite familiar with this expression (I've even heard someone invert it to give the reverse meaning). I'm very surprised that there are so few hits on the internet.