Full disclosure here...
I have done a LOT of job evaluation in the NHS over the years (both Whitley Council and AfC).
Here's an extremely brief summary:
The scope and range of roles is absolutely staggering
Having seen these jobs from the inside out you could never doubt the value of a medical photographer, a medical devices engineer, a therapy services manager, a catering assistant, a consultant's PA or so many other roles
People get paid more predominantly for having expert knowledge and skills, and dealing independently with risk; for dealing with distressing situations and for working unsociable hours
People tend not be paid more for being exceptionally busy, being nice, being hard working or being especially good at their jobs (unfortunately)
It's not really the jobs that are the problem when things go wrong. It's the over-accommodating manager who is untrained in holding others to account, it's the supervisor that lets people away with stuff, it's the absolutely ridiculous sick pay scheme and culture, and the prohibitive redundancy scheme
It's the sneering attitude of the general public who are oblivious to the billions of pounds being spent, the millions of patient episodes happening, the thousands upon thousands of staff involved, and the level of organisation and record keeping that goes with this. People don't want administration but they also what a system that's accountable to the nth degree... necessitating. Lots of administration.