a) Retirement implies withdrawing/retreating from mind/memory. That's impossible within a moving system; which sets mind/memory/momentum forwards.

b) Work implies energy (internal/inherent power) and the power within energy implies temporary growth (life) within ongoing loss (inception towards death); hence working till death.

Sleight of hand: "Arbeit macht frei" aka work (energy) will set you free (will of choice).

c) Working for others towards retirement implies the suggested temptation by few to tempt consenting many to work themselves to death in hopes for benefits.