Lack of recognition
Your best employees need recognition, and if you are failing to do so, they will eventually quit. In case you don’t any monetary ways to appreciate them, you should always make them feel good with constant positive feedbacks. A word of appreciation really matters.
Sudden hierarchy
If you suddenly ask your best employee to report to someone else and follow a chain of hierarchy before reaching you, he/she will feel demotivated. If you take away decision making powers from a person, it will affect the performance and build in frustration.
Profits over people
If you want to retain best of talent and employees, learn how to win your best employees first. You balance sheet will improve automatically.
Stagnation
After spending good 2-3 years in an organisation, every employee expects growth. Everyone wants to be growing professionally. If you can’t give growth, they will get it at some other place.