The biggest reason is time. You only live once and basically no one looks back on life and says "I wish I spent more time at work."

Second is benefits. Lower pay in exchange for benefits. These can be literal benefits like health insurance, or quality of life benefits like shorter commutes or work from home or paid travel, whatever you value.

Third is feeling valued. I've left better paying jobs that treated me badly for work that made me feel appreciated every day! This isn't just an ego thing, it can affect your health and general happiness in positive or negative ways. Work satisfaction is really important.

Fourth is growth potential. My spouse hit a pay ceiling where raises were basically never going to happen. Took a pay cut for 2 years and now makes more than before.

And there are probably more reasons.