Exposing yourself to hardship doesn't always make you immune to it

It is often wrong to assume that if your body doesn't like something then by exposing it more to that thing it will get used to it.

This holds true in the case of exercise, your muscles become stronger the more you use them, your bones and skin become thicker the more you put pressure on them. But not all processes in our bodies have a mechanism for self-repair.

If your body is allergic to something, then you will become more sensitive if you expose yourself to more of it.

If you are sensitive to cold temperatures, then you will become even more sensitive to cold if you expose yourself to it. Your body will not become adapted to it. If your headache is triggered by something, such as flickering lights in my case, then exposing yourself to flickering lights will make the triggers worse.

Certain phobias and traumas often get worse the more you expose yourself to them.

"What doesn't kill you makes you stronger" is not always correct. Sometimes things eat at you and weaken you.

Injury in your lower back is often irreversible.

Sometimes correcting mechanisms are weak because evolution did not catch up yet with new traits.

Some scientists believe that the reason why back problems are so prevalent among humans is because we have only been standing in our upright posture for only a few million years. There hasn't been enough time for a correcting mechanism to evolve for our backs in case they are injured.