Why do people end up as drug addicts?

The war on drugs is a disaster. Not only did it fail to reduce addiction, it actually led to more people becoming and remaining addicted. And this is only the tip of the iceberg: The war on drugs perpetuates racism, increases crime and violence, puts shackles on science and is a waste of public money. The only way to fight addiction is to legalise all drugs.

https://www.youtube.com/watch?v=jcu3X5yQHnE

They probably got it from their parents. Then they do it then their kids do it ect. Then it spreads around from person to person.