تعریف و معنای "the (odds|cards) [are] stacked against {sb}"

What is the origin of the idiom "the odds are stacked against someone" and when to use it?

The idiom "the odds are stacked against someone" or "the cards are stacked against someone" draws from the world of gambling, where the chances of winning or losing can be influenced by the way cards or dice are arranged or manipulated. In a figurative sense, it describes a situation where someone faces significant obstacles, challenges, or unfavorable circumstances that make their success or victory unlikely.