A husband has been married for 40 years. On the eve of their 40th anniversary, his wife complained that he never said to her "I love you" during this time. He said to her unabashedly, "I married you because I love you," and I told you, "I love you," when we decided to get married. So, if anything changes, I will let you know.
You encounter such characters in different places. People slink away from them because these characters find it difficult to praise, flatter, express love or appreciation.
At the workplace, you might have reported to a boss of this type, a boss who never praises or expresses appreciation of the effort done by his subordinates. Some managers do not even relay their assistants' praises conferred in their absence by the senior management. This praise might be all that those subordinates need as hope to go on. Withholding it affects their morale. As the great psychologist and philosopher William James said, "the deepest principle of human nature is the craving to be appreciated."
There are many reasons for withholding praise, such as:
1) Disengagement: some people are naturally disengaged. They do not want or cannot lull or be lulled by personal praise, flatter, or appreciation. But it does not need significant self-transformation to give kind words of praise where needed. "kind words do not cost much, yet they accomplish much". Blaise Pascal.
2) Envy: your enviers will not praise you, congratulate you for achievement, or show genuine appreciation for helping them. Sometimes they will do so if they must, but if you pay enough attention to their body language, you will see subtle gestures of resentment behind the mask.
3) Wrong philosophy: Some managers are not envious or insecure, but they believe that if an employee does what she is supposed to do or even has gone the extra mile, that is expected of her. But if she does wrong or fails to achieve the target on an isolated occasion, he will apply the corporate enforcement measures. He thinks praises are not warranted for doing the right thing, however perfect it is. Achievers need commendation to help them sustain, bypass expectations and increase diligence to avoid a negative outcome. "I can live for two months on a good compliment," Mark Twain.
4) Insecurity: some managers withhold praises or appreciation because they think compliments could motivate their subordinates to be better, encourage them to grow in skills and knowledge. Their fear is this growth could render them unneeded or replaced.
5) High standards: Some people do not praise others because they look at others' achievements as "normal" and "not above standard." On the other hand, they are managers or executives who genuinely have high standards of things, and they withhold praises until their expectations are met. However, the honest and dedicated exerted efforts could still be praised even if the outcomes were substandard.
People in workplaces sometimes make mistakes and err in their judgments. But if their errors are the exceptions, not the norms, and they are doing the best of their effort, there is no reason not to express appreciation for their work explicitly.