The first thing you should figure out about a new employee is not what they can do...but rather who they are.
Most employer-employee failures happen as a result of culture misalignment, not the inability to do "the job". So, ask yourself why job descriptions are largely task oriented, why interviews focus so much on experience and why we spend so much time showing someone how to do it. Instead, spend more time getting to know what makes someone tick, understanding their world view and what their dreams are...this is the stuff that counts in the end.