One of the side effects of judgment is that it reduces your ability to change.
When you judge someone else, you are in effect deciding that their approach or method is wrong, and therefore also usually deciding that how you do it is right.
As you continue to judge, you become more and more entrenched in your side.
If you’re at a concert and you’re poking fun at the people around you for acting excited at a level that seems unfitting for the circumstance, then even if later on you start to feel some of that excitement too, you are more likely to hold yourself back from joining them in jumping up and down.
If you constantly judge others, even if you never say those judgments out loud, you can start to feel like changing your mind and going over to their side would be letting them “win.”
So you don’t change, even if you have the urge to.
In the end, those judgments you’ve been making against others – the judgments that at least for a bit can make you feel superior – can cause you to be the one who misses out.