A guy I used to work with went on a ski trip (Vail or some shit) with his gf and some other friends. They had fun, ski'd a lot, partied, etc. His flight back wasn't until the next day after everybody else left so he decided to get one last day in on the slopes. On the last run of the day, near the top of the mountain, he tore his ACL. Realizing he was going to freeze right there on the mountain unless he could make it down before the sun set, he then had to shimmy his way down the mountain and told me could hear the other ligaments in his already weakened knee popping and snapping as he shuffled his descent. His shit was totally fucked when all was said and done.
And the last time I tried to do last try on a skate session, I ended up with an internal hematoma on my quadracep muscle. Seems like part of the game is knowing when to quit while you're ahead.