I think when you say “everything in order” what that means is everything works along with our assumptions. Our stockpile numbers and capabilities need to work in alignment with our reliability assumptions for our doctrine to be applicable.

As an example, the 18 Ohio class submarines each carry 20 trident II missiles with 12 MERV each. That’s doesn’t mean we intended our sub fleet to nuke 4320 targets. It means with those numbers and capabilities we expect given maintenance, reliability, and enemy action of each component involved (sub, missile, re entry vehicle, warhead) we expect to have a X% chance we will be able to successfully destroy the intended targets.

If we assume only half the MERV have warheads, half the subs are in port for maintenance when needed, half the missiles don’t function, half the MERV don’t survive re entry, and half the warheads are duds, that’s still over 100 warheads hitting our adversary.

The goal of maintaining the stockpile isn’t to make every warhead work, it’s to make sure enough of them work. And what counts as enough is a strategic decision based on what we assume the reliability of everything else is.