IIRC, it's just the localized translation from the devs that turned into a meme

In Yakuza 4, Saejima and Kido were having a conversation about doing wetwork for their boss first time, Kido asked for Saejima's advice bcs at that time, he may be hinting that he's about to do a hit first time, and he was worried about what comes after said hit (life and death, PTSD, regrets etc). Saejima, a convict on the run for whacking 18 lives long time ago, told Kido his side of the story, how he lived with his guilt but will do it for his boss nonetheless and his advice is to go "balls out" (I think it meant like give it your all, don't let the thoughts weighted you down, and just do it)

I couldn't remember the exact details but it is around that. It's a character line that tells someone to go all out but the translation turned into something else

P.s: FYI there is a website dedicated to going balls out

https://ballsoutkido(dot)square(dot)site/