I came across the following interesting quote from non-other than the current World Champion, GM Vishwanathan Anand of India.
"Nowadays, when you're not a grandmaster at 14, you can forget about it."
There are more quotes from him and other famous chess players at the following link http://www.chessquotes.com/player-anand
I had the opportunity of meeting (and playing against) Vishy Anand when he was just an IM at the old MAA building. I remembered we played blitz and I was handling the Budapest Opening using the white pieces. I lost - terribly and after the game, Anand showed me a simple move which would have made me won a piece out right in the first few moves of the game. I laughed about it.....