But you dont know the value of anyones labour really till you employ them and if they arent good enough then you get rid of them.
But you can make a good judgement via a recruitment process though, especially when you have a floor price for labour which covers a wide range of abilities, experience and education.
You can see it in supermarkets compared to 15 or so years ago, being able to work in multiple areas used to be a rewarded bonus, now people who are unable to multiskill dont even get in the door...