There is one relatively simple thing that every manager can do for employees but so few do, and that's give feedback. Normally the excuse is that they are too busy, but some studies suggest that they are just plain uncomfortable about doing so.
While their direct-reports want it, most bosses are too squeamish to sit down and discuss an employee's performance face-to-face. The importance of this is discussed in this excellent article over at CIO.com
According to author Esther Derby, "Feedback—when it's done well—can improve results and strengthen working relationships. When it helps people see their blind spots and understand the impact of their behavior, feedback can change the trajectory of a career."
Some managers claim that, in addition to being uncomfortable with the concept, that their attempts to give feedback often go astray. Derby states that managers report stories of "mysterious hints, vague announcements, arguments, blame and humiliation."
Derby's article goes into great length explaining the reasons why giving feedback is not only something employees want, but is crucial to a well-run department, company and office. She also explains exactly what feedback is, and that giving it needn't be so terrifying and time-consuming.
In short, one very simple way to improve the way your employees work for you, is to talk to them about the work they've already done.
Giving feedback is not just something to do when raise time comes, but something valuable throughout the year. Keep it in mind, and you may see improvements within your company sooner than you think.