Everything is very simple and everyone should know this. ERC-20 tokens can have a smart contract with which the creator can freeze or withdraw these tokens from your Ethereum wallet. I know such an example. Not all tokens have such a function, but because of the frequent cases of fraud, the creator assumes the function of a regulator in this chaos of decentralization. This is both good and bad. In any case, if you are not involved in fraud, then you have nothing to fear. Otherwise - study before use