Strange habits show up when people who care about each other get into arguments.
Perspective can evaporate, goals can change, and shared values can get ignored by both parties at the same time. Emotions flaring during an argument can cause core principles and higher purpose to quickly fade into the background and get replaced by one obsessive objective: to win.
A married couple can argue over an issue, even of no meaningful importance, and care almost exclusively about winning. Out-dueling the other. Proving their point. Pummeling their opponent (spouse) with impenetrable logic and undeniable emotions.
What do either of them win? Nothing.
There’s no trophy. There’s no real reward, just an imagined one. The selfish satisfaction of feeling superior and justified.
What do they lose? Understanding, appreciation, perspective, connection, and feelings of love. In other words, what they both want most from each other.