You’ve heard of golden handcuffs, but what about product handcuffs?
When you learn your company’s product so well that your value in the job market is much higher at the company where you’re already employed (and have been for a while).
If you were to move, you’d be at the bottom of a new learning curve. So you stay where you are because you’re “unconsciously competent”—the work has become so easy, almost mindless, and your output is still better than your peers even if just because you’ve been there longer and you’ve spent more time with the product.
So your company is willing to pay you more to stay than any other company is willing to pay for you to leave (and for the time you’ll spend climbing a new learning curve).
At some point there’s a trade-off between compensation and learning new skills, change of scenery, mission you actually believe in, etc.