If you go by job title and responsibilities alone, the job may well get done. But how the job gets done is another question. Are you actively doing something wrong, or are you failing to actively do something right?
For top of the line service and safety onboard it ultimately comes down to not 'what' is done but 'HOW' it is done. Without this information you or a recruiter can be looking at the wrong things in crew and missing the right things. RESULTING in less than perfect candidates.
"Why am I paying to just get a slew of CV's."
While there is no simple answer the fact is that any new employee will always be a risk. This is good reason why many top companies use a two, three or four interview selection process for their top positions. Along with this they integrate various tools to help create deeper dialogue with applicants so they can see how they work best, and if this fits with the company culture.