Keeping your best people is not easy - in fact, it is one of management's most important challenges. The cost of losing and replacing good employees is shocking - and minimizing the stress and expense of unwanted turnover is often a matter of adjusting attitudes and corporate culture. Some issues to consider and get right:
The Boss - generally, people don't leave jobs or companies, they leave bad bosses. Abusive behaviour, poorly thought out communications, failure to delegate or develop staff, conflicting and confusing goals, office politics, poor morale, lack of honesty and transparency... and this is the short list.
Recognition - no one likes to be taken for granted. Find ways, both publicly and privately, to tell your employees that they are important and their work is respected.
Sense of participating in a respected team - top people are "top" in part because they take pride in succeeding. For most people, succeeding in a team environment is particularly rewarding.
Poor work/life balance - some jobs require a commitment that drives out all other elements in life. Few people will happily accept such pressures for long.
Opportunities - top people are almost always ambitious. They are looking for opportunities, and if opportunities do not exist within their current company, they usually do elsewhere.
Money is a maintainer - not motivator. Focusing on money as an overriding motivator is a major mistake, and a risky strategy. Unintended negative consequences often follow an over-reliance on money as the core strategy.
No one listens or respects - people work for money but they live for recognition. If management neglects or fails to recognize the value of the employee, he/she will seek it out elsewhere.
Recognize that everyone works for himself or herself - one important key to success is to get people to work for you. The goal is to provide a reason why their best strategy is to work for the organization - otherwise they will simply work for themselves.