a person doesn't need to study to become a great artist, several months ago i literally said "i want to draw", bought a tablet, and found that i was pretty good at line art. i'm no mindchamber (yet ;P), but i draw well and enjoy doing it. something else that makes a good artists is being open to criticism. if you just block everyone out who doesn't think you're a god, you won't get anywhere. i am very open to criticism and it has already taught me how to shade decently.
and to the guy who's being a douche and saying that the OP needs to study, shut up. not everyone learns the same way and telling someone to learn the way you do could make them completely lose interest. i know if i was practicing art every waking moment, i'd be bored after a week. just back off and let people do things for themselves.