Because I was bored, and getting high feels so nice!
Boredom, depression, and the good feelings drugs provide are usually what causes me to want to get high.
I don't think I am depressed anymore, but life is still a big bore.
I'm also physically addicted to poppies, so I have to use those daily unless I want to get sick. I usually don't use enough to really get high, just enough to keep from getting sick.