Ah, the joy of being a woman. You can spend your whole life committing to getting extremely good at something, yet one day, a kind man can let you know that actually? You’ve been doing it wrong. This is how you do it instead.
Sarcasm aside, this is what’s known as mansplaining: when a man assumes the woman in front of him knows less by default and proceeds to explain the thing to her in a condescending, often inaccurate way.
