Great question! In this office, a 'Burnout' isn't something that just happens to you—it's something you have to earn.
To trigger a Burnout (Prestige), you need to reach the very end of the office supply catalog. The final item (Item #30: The Large Red Panic Button) is your ticket out of here. It costs 2.5 Quadrillion GP.
Once you buy and trigger it, you'll reset your progress but gain a permanent 'Severance' multiplier for your next Monday. Keep grinding, employee. You're not exhausted enough for the board members yet!