What is the hidden fee on Binance?

Could you please clarify what the hidden fee on Binance is? I understand that trading fees are typically disclosed upfront, but is there an additional, unadvertised fee that users should be aware of? If so, how does it work? Does it apply to all transactions, or only certain types? Is there a way to minimize or avoid this fee altogether? As a cryptocurrency investor, it's important for me to understand all associated costs before making any trades on the platform.