Perhaps I was less fortunate than you in the teachers and managers that I had, but my experience is that often teachers are no more competent at teaching than some managers are at managing and some interviewers are at interviewing === not very competent at all and sometimes abusive and harmful to the student's development.

Except where I have had one-on-one tutoring/mentoring (rarely), the presentations I have had were often not well suited to my own learning style and ability. In some cases I would go so far as to say they were not well suited to anyone in my class.

I'm fortunate that I do quite well reading manuals and texts - it's my preferred method of learning, after hands-on experience. But I know some very intelligent people who cannot read manuals - they can learn, given appropriate presentations, but they can't read or, at least, their ability to read and learn from lengthy texts (relative to twitter) is so limited that they habitually seek other sources of information and simply ignore manuals and books and strongly resist reading them even when pressured. In some cases, pressuring them to read would be highly counter productive.

Without knowing the specifics of the case, it is a bit presumptuous to assume that every student has already had the benefit of ideal, or even reasonable presentation of the subject matter by the time they are given a homework assignment or attend a job interview, or that they are learning in the context of an ideal, or even reasonably effective study plan. My experience is that sometimes the prior presentations are grossly inadequate. I also have met teachers (hired and professionally responsible for teaching) who did not know their subject matter sufficiently to be effective. Yet their students were better off for their willingness to do their best to teach despite their limitations and there were none better available. Not everyone lives in areas so well endowed as North America and Western Europe.

Everyone needs help to learn and develop their abilities. While I agree that those who have not achieved a required competence deserve to fail assessment of that competence, I don't think that equates to their not deserving any further help.

Rather than saying that any intercession is ineffective, I would say that if one is truly interested in teaching one must learn the specifics of the case, including the abilities and past experience of the student, and continue by developing teaching plans that suit the student's needs. Refusing to answer questions or berating the student for not having read the documentation without knowing these specifics is unlikely to be effective.