"Mentimos mejor cuando nos mentimos a nosotros mismos."

Simplified Meaning:

Sometimes, we convince ourselves of things that aren't true, and we do it so well that we believe our own lies. It's like when someone doesn't study for a test and then tells themselves they don't need to study because they're already smart enough. They might really believe this and, as a result, not study at all, even though they know deep down it’s probably not true. It's easier to believe a comfortable lie than to face an uncomfortable truth. For example, someone might tell themselves they're happy in a job they dislike because admitting the truth would mean they'd need to take difficult steps to find a new job. By lying to themselves, they avoid facing challenges or making changes. If you want to avoid this trap, it's important to be honest with yourself, even when it's hard, and to face reality head-on. This way, you can make better decisions and improve your life.