Unfortunately it doesn't seem to make much difference. I have seen graduates get jobs who had stumbled through both their ground and flight exams with plenty of partial passes and re-sits. Meanwhile the ace of the base doesn't seem to get a look in.
There is a huge lottery aspect to first jobs.
Obviously the better you do on a course the better it will look if anyone at interview is that interested to check. That said a failure along the way in training can provide a useful talking point at interview along the line of "How I address failure and overcome it".
There are PLENTY of very fine pilots out there who fluffed part or all of their IR. Similarly there are pilots out there who stumbled through their IR on a fine day, on the route they practiced most on a day when the examiner was in a good mood (probably a blue moon that evening). Its not really a very good measure of how 'hot' someone is or how they would perform on a conversions course.
Thats really the job of the Sim Assessment. The interview should be about you, your personality and how your aspirations fit with that of the airline.
Try hard for first time passes and 85% - but don't sweat if you blot the copybook.
Cheers
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