Today's world is too complex to stick to one point of view for too long. If you want to be right a lot of the time, you need to change your mind a lot of the time. In an interview with the Wall Street Journal, Charlie Munger, Warren Buffett's business partner, said the following:
“Part of the reason I’ve been a little more successful than most people is I’m good at destroying my own best-loved ideas. [...] I’m pleased when I can destroy an idea that I’ve worked very hard on over a long period of time.”
It's hard to change your mind. Firstly, it means admitting, even if only to yourself, that you were wrong and might have made a mistake. Secondly, other people are often critical of those who change their minds. Society still sees consistency of thought as a positive virtue even though it's probably not.
Thirdly, some people stick so heavily to a particular opinion that it becomes part of their identity. This is particularly prominent in politics, where you are a Democrat or a Republican. It's much harder to change your mind about something if it's part of who you are.
But your opinions change. You act on imperfect information. You read things online that are biased or misinformed. You live in a world that changes so fast it's hard to keep up. All these factors mean that it's not just okay, but necessary to change your mind.
Because isn't the truth important? Aren't you doing yourself and the world a disservice if you believe something that isn't true? Set aside your ego and don't let others dictate what you should think. It's amazing how much freer you'll feel when you give yourself permission to change your mind.