People learn best not when were taught nicely or while their faces were blooming with smiles and laughs, like this world is devoid of constant massacre and the ever increasing fuel price. No, they don't.
People learn when:
1. Someone dies.
2. Volcano erupts.
3. It's too freaking late.
4. It's too freaking useless to learn.
5. Time gets nigh.
6. Banana fruits twice (Google it).
As you can see from the list, people usually, if not most of the time learn best their lesson only in critical moments. In a rather harsh terminology, when they are in deep shit.
In a different conclusion,
I'm in deep feces and therefore I learnt my lesson, the hard way.