If something yields the result we want even once, it’s human nature to do that exact same thing again. In general, people are creatures of habit. Just think about how many times you’ve gone to your local coffee shop and ordered the exact same latte. Once you found the mixture of ingredients that your taste buds enjoy the most, you probably chose to stick with that.
However, in business, this “stick to what you know” mentality often means that companies hire the exact same type of employee over and over. The thinking is often that if employee X is doing a great job and everyone gets along with everyone, that the smart thing to do must be to hire more people exactly like them. This mentality leads to hiring managers seeking out candidates that identically mirror their existing workforce. They’ll look for the same educational background and skillsets, source from the same narrow list of companies, and look for similar personality traits during interviews. Before you know it, you end up with an entire staff that looks, thinks, and — to a degree — acts almost exactly the same.