How did Arul Kumar discover facebook bug?

[Intellectualriddle889]

FB awards Indian engineer for spotting bug --------------------
An engineer from Chennai, Arul Kumar detected a security bug which could delete images on FB Reward =$12,500!

http://in.screen.yahoo.com/facebook-rewa...52344.html
http://arulxtronix.blogspot.in/2013/09/d...ok-by.html

How did Arul Kumar discover facebook bug?
Many people including engineers must be surfing facebook but what thing (quality) made Arul Kumar detect the bug?

Which personality traits / speciality (including the fact that he is an Electronic Engineer) does he have? Any guesses?
My intention behind asking this question is to get inspired from the boy.

[?]

He used his brain, and his human body.

[Another Guy]

It would most likely require an extensive knowledge of web-based coding/programming languages. Those typically involved in this sort of thing would be PHP and/or JavaScript. But, it could also be Ruby on Rails (although to my knowledge, Facebook is coded in PHP and JavaScript, not Ruby).

[pri✍]

Have the knowledge & brain (the tools) and perseverance to see & analyze every detail, systematic, focus and determination, put all the heart & mind to do what he do.

Knowledge alone achieve nothing like a knife can cut woods, but carving it need more than a knife (knowledge) to do it, it need dedication & heart too.