Anywhere where you are tired, cold, hungry, distracted, in danger, sick, without a companion(s), thirsty, unfamiliar with the area, a prisoner or where people are unfriendly. That about covers it.
OP - one size does not fit all.
You can probably guess what most people are going to do -
1. run home;
2. run to school to pick up the kids;
3. hit the liquor store/drug store;
4. hit the grocery store;
5. join the congestion on the freeway.
6. get weak within a couple of days from a lack of water or food;
7. start fires that quickly get out of control (fire doesn't discriminate between urban structures and the dear, safe woods, wheatfields, or cabins under pine trees.)
8. get sick from bad water.
So long as you:
1. have the ability to go to ground in place for a few days;
2. anticipate how you will deal with fire at home (roofline sprinklers, dispose of trash, cut trees overhanging roofs);
3. have water and a way to clean water;
4. have companions;
5. have plans;
6. have basic life necessities for you;
7. have a modicum of food;
8. and a means of backup transportation like a bike,
you have dealt with shtf.
Every football game is tied at the kick off. So is survival when shtf. The person who has skills, physical health, mental conditioning and some equipment will be up the food chain and the survival chain.