Why Do Koreans Use 반발 (Casual Korean) to Korean Learners? | A Glass with Billy

It's essential to use formal and honorific speech (높임말) or polite speech (존댓말) when meeting someone for the first time. The same applies when talking to strangers, teachers, co-workers, bosses, and in any situation where you want to be polite. But then why do native Korean speakers sometimes use casual speech (반말) when meeting non-native Korean speakers?

It happens online, as well as in person. Has this ever happened to you? What did you do? What did you say?

I talked with my friend about what we've done, and what we recommend doing - as well as what we recommend not doing if this happens to you.