The phrase often relates to keeping strategies hidden in competitive situations.

Strategy Concealment

Used metaphorically, referring to plans or intentions rather than actual cards.

Metaphoric Use

Suggests carefully deciding when to reveal information.

Specific to card games as a necessary action at a game's conclusion.

Directly relates to the physical act of revealing cards in a game.

It implies being open about one's feelings or thoughts.

Revealing one's hand can make one feel vulnerable or exposed.