For a while now, I’ve been blaming insecurities and an unclear sense of self as the root causes for most problematic behaviors. Condescending people are no exception.
condescending: having or showing an attitude of patronizing superiority
Why would someone talk to you like your age is a single-digit number? Granted, some people objectively know more than you in certain areas. However, I’ve noticed those who actually do, are usually humble and simple-minded people, willing to share their knowledge and experience without ever being cocky or patronizing or trying to seem superior.