As with any course, if the instructors (in this case the FIC instructors) are putting their students forwards for test and they are not ready for the test, it is the instructors who are at fault.
One of the low points of my instructing career was when one of my students failed his PPL test. He was quite ok about it - he knew that he'd screwed up, and didn't expect anything else. But for me, it was a dreadful feeling, and not something I ever want to repeat.
If I become an FIC instructor in the future, I can't see any reason why this attitude should change - if someone is not going to make a good instructor, they are not ready for their test, and they need to sit down with their FIC instructor and sort out the problems. If they are going to make a good instructor and are prepared for the test, then they should pass.
As Ready says, it is possible to have a bad day - but even so, the fact that you've been put forward for test should mean that, bad days aside, you are ready for the test and the responsibilities which come after that.
FFF
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