Rewards and Achievement.

Rewards are very powerful in the short-term in getting people to behave in the way, you want them to act. People may actually feel more focused, but the focus is typically more  narrow than when no rewards are involved. This helps only in doing manual jobs where little thinking is involved. However rewards change in a negative manner the way we engage in a given behavior. We do exactly what is necessary to get the reward and reach the desired goal and no more. So we are less likely to notice or remember things that are not immediately relevant to what we are doing. Kids were given different colored cards and had to memorize all the words. The kids were unexpectedly asked to recall the color of the card that corresponds to each word. Kids who were promised a prize had more difficulty in remembering as rewards undermine this 'incidental learning '. In another experiment ,one group of people  were  asked  to do a task , and another group were promised a reward for doing the same task  well. The group that was not promised a reward did much better. Also people who were promised bigger sums of money did worse than those who were promised small sums of money. The explanation is that problem solving and non-manual tasks need more exploratory and creative  thinking and  so need a wider focus.A salary is not a reward but ' compensation' for work put in. And still if employers want to promote creativity and excellence that must pay well and then do their best to take their employees minds off money.  
  Rewards narrow our focus. Creativity is stifled because people need to feel self-directed and autonomous and people  experience  rewards as controlling. The objective is to succeed in obtaining the reward with as little effort as possible. So people will choose easier tasks avoid risk taking and  challenging ones and spend the least amount of time as possible. Rewards are problematic even when used with tasks that are less interesting than others. Not only do they reduce interest in the task itself but also in strategies  for reconfiguring a dull task and brightening it up.