Yield Optimizer fees are taken based on generated user profits. This is called a performance fee. There are no management or deposit fees. There is a minor withdrawal fee used as security mechanism against certain kinds of JIT MEV. For instance an attacker would deposit funds right before a vault gets harvested and would thus earn yield without "working" for it. The withdrawal fee is send back to the vault and is therefore eventually distributed to all vault participants in form of user profit. There is also a harvest fee that the caller of the harvest function earns in order to incentivize decentralized execution mechanisms. The amounts of fees described vary per vault and may change over time, depending on the generated vault yield, its TVL, and required gas costs.