Game Theoretic Analysis
Let's try applying a spot of Game Theory to the scenario.
When the game is Global Thermonuclear War, the electrician charged with the job of wiring up the big red button on the President's desk has a set of choices that go something like this:
* If the other side has already fired, and their launch was successful, you're toast anyway. It does not matter whether or not your launch is successful.
* If the other side has already fired, and their launch was unsuccessful, history is unlikely to look kindly upon you if you launch a counterstrike.
* If the other side has not already fired, and your first-strike launch is successful, you are going down in history as the baddie.
* If the other side has not already fired, and your first-strike launch is unsuccessful, the world is saved from nuclear annihilation.
One of those outcomes is so much less undesirable than the other three, it overrides any pride in a job well done. The thought of potentially never having to cook again, and for the right reason (every restaurant in town is desperate to have the hero who saved the world from nuclear annihilation as a customer) as opposed to the wrong one (being dead) even overrides the fear of a bollocking. Not that the job you did can even be tested in any meaningful way. Verifying the integrity of the cables from the power supply through the switch to the ignition system necessitates disconnecting the actual ignition system, and enough sundry poking about with stuff that nobody is likely to notice you slipping a wire back into the hole you were supposed to have put it in the first time, just for long enough for someone to hear a multimeter go beep.
And now remember that in real life, there isn't just one person responsible for the job that is orders of magnitude more complex than the heavily-simplified version I just described, but hundreds, if not thousands; every single one of whom has a stronger incentive to sabotage it than to do a good job.
Icon -- "Look at what you could have won!"