Motivate people with positive feedback and they will strive to do better next time.
Motivation is somehow like God: everybody thinks he knows a great deal about it, but no one can tell for sure what we are dealing with. When big corporations appeared, they didn't have the slightest idea about motivation. No one had heard the phrase 'productivity in the workplace.' Big companies would never have bothered with this wonderful concept if they hadn't noticed that there was something rotten in the state of… their employees: they seemed to have problems with fully fulfilling the tasks that they were assigned. That is why they came up with the idea of motivation, not because they cared about their employees, but because they had to increase productivity in the workplace.
They discovered two major ways of motivating their staff: a positive and a negative approach. They tried to implement the negative approach, as it seemed to be simple and it needed little time to put into action. They started putting pressure on their employees and it worked almost instantly. However, on the long run, this idea proved to be worthless, as the people started to feel more stressed and soon enough they started looking for jobs in a better environment.
When the negative attempt failed, they looked to the positive. That is why positive motivation overrun the negative one. According to modern psychology, a positive stimulus will always produce a positive feedback, while a negative one will rarely produce a positive feedback. Therefore, luckily for the employees, the corporations have taken up the positive way of motivating their staff and productivity in the workplace increases as a result.