Guys, please consider the statement: "You may not be able to stop everyone from leaving your firm. You need to ensure you remain their best employer," which actually matters here. I agree with (Cite Contribution) Ma'am. No need to ask the employee whether he/she is planning to change jobs or not because you are not going to get an actual response and the answers you want. For example, if I had been asked the same, I would surely reply to my boss, "NO, I'm not looking for changes; it might be a rumor." This is a natural and most expected answer from an employee. Therefore, it would be better to know the reason behind the decision of any employee to look for a change instead of asking directly.
There are many programs and systems available that you can use to motivate and retain your employees, such as [I]feedback system, Transparent Work Culture, Supporting employees, Responsibility with more Flexibility, Stress busters, and so on...
Actually, the subject of this thread/post could be "How to retain employees", and I guess we have already discussed the same many times before.