One aspect I find a bit frustrating about most, particularly current Government is when they keep blaming things outside their control. There are always things outside your control. You should be planning on the basis that unexpected will happen. Covid, Russia invades Ukraine, Trümp tariffs, US invades Iran, etc..
And they will keep coming eg towards the end of the Covid pandemic scientific experts were saying how there will be more, they are now a significant risk given our "relationship" with nature, not a question of "if" but rather "when" (I listen to several health strategy podcasts and doesn't sound like we're actually doing much to prepare, just "waiting on the outcome of the inquiry").
If your "Plan" is based on everything going well in your ideal world they you can be sure it will fail, likely fail badly.