On Solana, a token can keep a freeze authority. Whoever holds it can freeze the token in any wallet. Your balance still shows, but you can't send or sell. On Ethereum-style chains the same trick comes as a pause switch or a blacklist that blocks chosen addresses.
How scams use it
The creator lets early buyers in, freezes everyone once the pool has enough money, then sells their own tokens into it. Frozen holders can only watch.
Legitimate uses
Regulated stablecoins like USDC keep freeze and blacklist powers to comply with sanctions law. That's why we don't count these powers against tokens on the trusted list. For an unknown meme token, there is no good reason to have them.
Green flag"Freeze authority revoked" on Solana, or "Ownership renounced" on other chains, means nobody can lock you out.