I think you have a passion and an obsession for something when it's not necessarily ubiquitous.
Critics have their purposes, and they're supposed to do what they do, but sometimes they get a little carried away with what they think someone should have done, rather than concerning themselves with what they did.
I have had so many great moments, but I would have to say that dancing the Swan in 'Swan Lake' was such a unique and passionate experience for me. It was such bloody hard work, even at that very early age, that I would not want to try to replicate it again now.