A lot of occupations have high failure rates, and AEC is one of them. "Hard"? Some courses are, and there is a lot of work required to pass them, yes, but, aside from that, some people, no matter how intelligent, motivated, and talented, are simply not suited for those types of work.
Having your mind at ease is not a good thing now, on course, or on the job. Another term for that is "complacency".
And it's "Int" in Canada. "Intel" is American.