The power of saying no. I've always felt like the little white lie was great as a social lubricant - e.g., "Oh I'd love to come to your housewarming party but I've already got plans that day" when you know full well that you're available but you just don't wanna go.

But after a while, making excuses and remembering them later gets to be stressful. Especially for me because I'm horrible at lying lol. So I've learned to say things like "Thanks for inviting me, but I'm gonna sit this one out." It's a polite but clear 'no' and now I don't have to keep up a fib going forward.

To be fair, sometimes people don't like being told no, but I've been surprised to see that they'll usually accept it gracefully.