If you're constantly a burden to everyone else doing it on purpose or not do not matter, if you got any sense of decency you would realise that yourself and remove yourself from it and come back when you can bring more to the table than ruining the thing alone.
But since ppl do not care about being burden or dead weights and will stay even if they're the only problem here it's not surprising that at one point timmy becomes the punching bag and i can't say he did not deserve it at some point.
And you can be the kindest person on this planet, timmy wont miraculously learn this by your words alone. I guess it do happens, but it's way too rare in this game to even waste time doing it for every timmy each single time.
But i like the jp way tho and how they deal with it, just disband blacklist the guy and creat another one, at least timmy feelings are safe.