Well...

consider how much you develop from 16-19.. then from 19-25.. which would make more of an impact on your life if something was unknowingly misunderstood, possibly even abused. Same reason there are "legal" ages for alcohol and tobacco as well.

Kids abuse things...

Bob.
BobBong Reviewed by BobBong on . Why do people say "Wait until you're 18" I don't understand why people say "Wait until you're 18 to smoke weed, so your brain develops." That doesn't make any sense, your brain isn't fully developed until you're 25. I'm 16, I toke, and I still get A's in school. Rating: 5