piss in(to) the wind
To do something totally pointless, fruitless, or futile; to waste one's time doing something that will not or cannot come to pass. To be perfectly honest, I feel like voting is just pissing in the wind, so I just don't bother. My mom and dad spent years pissing in the wind trying to get my brother to take his studies seriously, and in the end he dropped out anyway to pursue a career in music.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.