>What you're missing here is leverage. Janitors don't make much money because most people are capable of basic janitorial tasks, and thus they have little leverage in the job market because they could be easily replaced.

Janitors often make more than you think (both in terms of compensation and benefits), because while their job is easily replicated, they also require a great deal of trust.

I think this concept can extend across all jobs - you're not just paying for skill. If someone is dependable and trustworthy, it might be worth paying a small premium to keep them around versus an unknown quantity.

Every time an employee who might have stayed if that had a slightly higher wage, you run the risk of a toxic person coming in.