Principles are ways of successfully dealing with reality to get what you want out of life.
Ray Dalio, one of the world’s most successful investors and entrepreneurs, cites principles as his key to success.
Articulate your assessment of a person's values, abilities, and skills up front and share it; listen to their and others' responses to your description; organize a plan for training and testing; and reassess your conclusions based on the performance you observe. Do this on an ongoing basis. After several months of discussions and real-world tests, you and your report should both have a pretty good idea of what he or she is like. Over time this exercise will crystallize suitable roles and appropriate training or it will reveal that it's time for the person to find a more appropriate job somewhere else.