Are you asserting that skills otherwuse differing only qualitatively are related by a ranking, based on the duration of time invested in acquiring them?
Are you using word salad to deny workers their lifelong earned skill sets by assigning an esoteric value judgment based on the level to which YOU deem it necessary for justice?
You deny someone their skill when you say they can't have more or less of it. If skill can be obtained and improved, then it can be more so or less so.