Because those letters in that formation weren't already taken.
Why is chess called chess?

chess (n.) 13c., from Old French esches "chessmen," plural of eschec "game of chess, chessboard; checkmate" (see check (n.)), from the key move of the game. Modern French still distinguishes échec "check, blow, rebuff, defeat," from plural échecs "chess."
The original word for "chess" is Sanskrit chaturanga "four members of an army" -- elephants, horses, chariots, foot soldiers. This is preserved in Spanish ajedrez, from Arabic (al) shat-ranj, from Persian chatrang, from the Sanskrit word.
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From: Cheating Engines Solves Situations (CHESS)...
wheres the h?
CHeating Engines Solves Situations...

Back in Medieval times, where it originated, for years it was called "chest". Floozies earning a sordid living in taverns would ask "Would you like to play with my chest?" As the sport grew in popularity and more drunks started using the term, it gradually got slurred into chess. It eventually turned into a board game (etymology: "bored" game) because the women got tired of being groped by drunks, moved on, and the drunks, suddenly bored, having no chests to play with, had no choice but to play "chess", which entailed sliding their little pieces around and spending a lot of time in contemplation. Coincidentally, the word "masturbation" was coined during the same era.

Back in Medieval times, where it originated, for years it was called "chest". Floozies earning a sordid living in taverns would say "Would you like to play with my chest?" As the sport grew in popularity and more drunks started using the term, it gradually got slurred into chess. It eventually turned into a board game (etymology: "bored" game) because the women got tired of being groped by drunks, moved on, and the drunks, suddenly bored, having no chests to play with, had no choice but to play "chess", which entailed sliding their little pieces around and spending a lot of time in contemplation. Coincidentally, the term "masturbation" was coined during the same era.
lol
I just dont know...