What is the margin maintenance fee?

Excuse me, could you kindly elaborate on the concept of a margin maintenance fee? I'm a bit confused about its significance in the realm of cryptocurrency trading. Is it a charge levied on traders who maintain a Leveraged position, and if so, how exactly does it work? I'm particularly interested in understanding the mechanics behind it and its potential impact on a trader's portfolio. Additionally, are there any strategies that traders can adopt to minimize or avoid this fee altogether? Your insights would be greatly appreciated.