Donut shit. Literally.
With a donation - you almost always get hit, almost always get a shot, you are practically not hit even at point-blank range, you are thrown into a team with a good rating.
Without donation - you miss even at point-blank range, you don’t even punch at point-blank range, even spitting will hit you, you’ll be thrown into the team with the lowest rating.
A simple example: a donator on a light tank of level 6 will win a 1 on 1 battle against a heavy tank of level 10 by the donator. Although according to the “numbers” of characteristics, it’s like a fight between a cardboard box and scrap steel. But the cardboard box is full, so the scrap will lose without a chance.
The game, using all the methods to cheat suckers for money, from the start slips premium donation tanks “for a while” for free, so that the player feels how easy it is to win for money. And then he selects and shows how much of a schmuck and loser the player is without a donation. This trick works for many and they run to pay for this scam.