Really there are two types of work: bounded and unbounded. In bounded work there is some well defined threshold where someone is good enough, or at least some f

Really there are two types of work: bounded and unbounded. In bounded work there is some well defined threshold where someone is good enough, or at least some finite risk from someone not being good enough. For example a mediocre mechanic might not be able to fix an issue that a better mechanic could, but the cost of going with a bad mechanic will never exceed the value of the car (at which point you would simply buy a new car), and realistically the cost will almost always be quite a bit less. For bounded tasks, it makes sense to hire average people who show up. On the other hand there is unbounded work where the skill level necessary is unknown and the costs of going with someone who is insufficiently skilled could be immense. For example odds are there's no way to know if your surgeon isn't up to the task before they've cut you open, which is a terrible time to discover that fact. For unbounded tasks it makes sense to always hire the best you can possibly afford, even for something that seems like it should not require much skill.