The primary mistake that I see, and hear, happening are failures to manage expectations. The majority of training available is merely "review" seminars which highlight what someone should already have learned during their "5 years of experience". Unfortunately, many companies are guilty of advertising ploys to make customers believe, in the onset, that their training is the "end-all, be-all" route to certification. Potential trainees should be aware of this and prepare themselves accordingly.
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