My highschool had personal economics courses preaching the 70/20/10 rule with saving 20% of your income for short term savings, 10% for long term. People don't

My highschool had personal economics courses preaching the 70/20/10 rule with saving 20% of your income for short term savings, 10% for long term. People don't follow it because credit(debt) is too easy to get and you can make impulsive decisions to blow money on vacations and other things. I don't know what the answer is but a highschool course isn't it.