Quote from OPTIONAL777:
First cigarette, humans naturally choke and reject.
First beer or alcohol, people generally hate the taste.
First drug, disorientation and loss of control which brings fear.
Experimentation is natural, but with drugs, cigarettes, alcohol, most people naturally reject the experience...but social pressure gets them to continue and then they become hooked on the chemicals...or trying to reclaim the experience of their first "high."
Or in the case of booze or drugs, they are often used to escape a reality that is painful...