Junior dev here.
I'm removing features that are worth days of work because business requirements weren't properly defined with the business owner. Disheartening.

@molaram Well, they're still on a branch but it'll never be used

This happens all the time, often but not always to junior devs.

Some od these demands may come from a client or higher up boss who just randomly changed his mind, so the giuy you hold responsible may actually be the person who had your back. Then again, some older people with influence genuinely believe that you're just a kid and it's their god given right to waste your time as much as they like. It's brutal but that's the reality. It's up to you to dispel this as quickly as possible.

Schedule some time with whoever that was even if it was your boss and explain exactly how much of your time they wasted and how easily that could have been avoided. Don't go behind their back or start a war, just explain it straight to the guy likely responsible. Also explain that it's not just a matter of working efficiently bur also a matter of common decency and respect.