It is common knowledge that people do not just have a bad day and fail upgrade training...there are always underlying issues, such as attitude. If you bust a ride and have a good attitude, they work with you.

But you never hear "he was a great guy, but he failed upgrade and got fired". It usually does not come as a surprise...

Again TW's situation seems unusual and I don't know the answer, nor do I believe in up-or-out. If there is a wild-card in the process, it would be personality conflicts.