I think the thing with a lot of birds is this: people expect that their default is "tame" when it simply isn't. Even little budgies are essentially still wild animals.

That doesn't mean its impossible to tame a budgie, but I would consider one that is very tame and people

friendly rare. An exception to the rule.

When you combine that expectation along with this idea people have that they are owed interactivity and friendliness from any animal they take in... well you get disappointment.

Little budgie doesn't understand that you're the reason

he's got a home, food, and safety. He probably honestly thinks you're a predator. You can't expect any animal to know and appreciate the fact that you took them in, and yet people still do.

So when these animals don't give them the friendship they feel owed, they get rid of them

Point is: Don't agree to take in a bird unless you're okay with the possibility that that bird may never be tame.

Or, be okay that taming them could take a lot of time with a lot of consistent work and slow progress.