Quite a number of Achievement systems games have come to mind when thinking about it.
- You just moved for first time
- You killed your first create
- You caught your first fish
- You just died for first time
I think most get robbed of the true feeling of success when they never had to work for it. I recall in Everquest we spend sometimes months of pure struggle sometimes to get a boss down or at least on farm. You killed something without struggle "yay..." You killed something after great struggle "WOOOT OMG YES WE DID IT AAHAHAHAHAHAHAHAH." We had a few screamers in Ventrilo back than. Sometimes people could not help but wake up the entire household if it was something really hard to defeat with how many they where in taking it down for first time. .
I just seen I had neglected to upvote this but took care of that just now. :D