A white Tiger in India has killed someone who jumped into his enclosure. India Tiger Tragedy: Photo Shows Delhi Zoo Visitor Moments from White Tiger Death
If he had followed the rules he would still be alive is my bet. It might well be, it sounds like it took some effort to actually get into the enclosure. Now I know why all the big cat enclosures I have encountered are human proofed.
If he went in on purpose, I'm still betting it's a suicide attempt. But yeah, enclosures aren't just to protect people from the animals, they're to protect the animals from people. If the people and animals had free reign to interact, I'd be far more concerned for the animals. (and to be honest, I don't really feel sorry for people who get bitten while petting a tiger or trying to cuddle a lion)
Overview of Tiger-attacks at zoos in India during the last few years : Six Tiger Attacks in Eight Years Across India's Zoos
Do you read the Darwin Awards? I don't know if it was confirmed or unconfirmed, but one woman won one on account of having gotten out of her range rover in South Africa in order to pose some wild lion cubs that weren't posed properly. I'm not sure how much of her they found afterwards.