Why are we not allowed to capture the King? Why do we have to corner the King in a checkmate? Why can't you kill him if your opponent did not notice that his king was in check? Because like in real life, killing the opposing King on a battlefield is not very profitable. It is much more useful to capture him alive and ask for a ransom, thus preventing a new King and getting a huge sum of money.
Also, in the era when chess was invented, playing a game where you won by killing a royal could have been seen as tantamount to a declaration of high treason.
Or perhaps you're taking him and his nation hostage, as a puppet state.
Can occur when analyzing a written record of an already-completed game. For example, if White won a game and looked it over later, White might see that if Black had played some other response at some point instead of the actually-played line, it could have been devastating and Black could have won the game instead due to White's mistake.
"The Story of Chess" can come off as an Irrelevant Song as on the main page, but it indirectly establishes that it's not so much about the game itself, but The Chessmaster in the story who is betraying his brother and manipulating his mother into agreeing with him.