Spend enough time in a soul draining job, suck up to the boss long enough and surround yourself with enough dark side co-workers.
Put your innovative ideas on hold permanently, switch your mind to autopilot (no upgrades) and crush free spirited thinking & creativity. Close opportunities for learning and engage in mindless repetition. Run away from technical arguments and challenging the status quo. Sacrifice values and morals. Fit in even when it goes against every nerve ending in your body. Forget about delivering your personal best. Do your work each day and go home. Tomorrow is another day of the same…
Guess what happens?
When you exit the current position, you will be dumber than when you started in it. If you are lucky; some dumb employer will employ you for a higher position and package.