Firing: How do you fire an employee that just isn't good enough? - Quora
Eric Barker stashed this in Work
Great math metaphors:
The best employees are multipliers who make others more productive, and next are the adders (workhorses). Subtracters are the good-faith incompetents who cost more than they bring. Dividers are the worst kind of problem employee: they bring the whole team (or company) down.
When you turn a subtracter into an adder, what you get is a very loyal employee: someone who was well-mentored and learned a lot.
Three years later, you might have a bona fide multiplier. I've seen it happen.
Treat the situation with gravity:
Whether it's the right thing for your business or not, when you fire someone, you are inflicting significant pain on another human being. This shouldn't make you change your decision but it should make you understand the gravity and do it with compassion. This person will have to go home to their friends and family and explain what happened and it may affect them significantly.