There’s a popular phrase in HR circles doing the rounds, about “Letting employees bring their best selves to work”.
Not only is it a nice idea, it makes economic sense. People’s best selves do far better work, than people’s crappy selves. Of course they do. For the same reason happy chickens lay more eggs than unhappy chickens.
i.e. When you’re happy, you give more. When you’re miserable, you take more. You don’t need to MBA to understand that, it’s just human nature, plain and simple.