Most entrepreneurs underestimate the challenge of hiring someone for a founding role. I know I did. The roles that end up becoming some of the most influential in a startup often stay in the hands of those who come onboard as founders. So it's important to get the makeup of that core team right. Whether it's a sales director, customer success head, or lead engineer you're looking for, there are a few principles that can help you make the right decisions for the long haul.