When we do things for others, most people expect some sort of recognition. Payment, a thank you, maybe a future favor. This may simply be human nature, an unwritten rule of reciprocity. As long as the give/take remains balanced there is seldom a problem. Problems sometimes develop over time when either or both parties fail to understand fully.
For instance, an employee always comes in on time and sometimes stays a bit after. They never miss work and always do a good job. The employer may feel the employee is paid for their effort so everything is fine. The employee may feel they are going above and beyond and have built up a measure of "good faith."
One day the employee ask a ‘favor’ and decides it’s time to cash in. To him this is quite understandable. They ask for a day off, the employer can’t grant the request and ill feelings pursue. This may be forgotten in a few days or can result in, "After all I’ve done for you," feelings. It can even escalate into a good employee leaving the employer, taken to extreme.
Some of the best employers realize this. Rather than letting these gestures accumulate, they try to reward them as they go. By this I mean recognizing extra effort. Regular thanks and even monetary rewards for extra effort can help keep the ‘psychological books’ more in balance. As an employer, doing just a bit more than expected can be a good investment in harmony.
As a great employer, perhaps it is wise to always give a bit more than we take. It may also be wise to guard against expectation of gratitude; just the cost to be the boss. Perhaps Dale Carnegie put it best when he advised, "Expect ingratitude."