What does efficiency mean? Due to economic problem is a scarcity of resource, efficiency is concerns with the optimal production, consumption environment. For time pressure consumption situation example, e.g. supermarket shopping counter check out purchase queue waiting time pressure, cinema purchase ticket queue waiting time pressure, restaurant queue waiting booking table time pressure etc. different consumption pressure time waiting situation. For time pressure woring situation example, e.g. supervisor's demand tasks finishing on time before the employee leaves the office on the day, then the supervisor's demand will cause the employee feels time pressure to do all tasks on time, otherwise, he needs to work overtime, even no extra allowance compensation to his extra time loss, or the employee needs to do another employee's tasks, due to he is absent on the day. However, this situation can be called economically efficient production or consumption if: no one can be worse off, no additional output can be obtained, without increasing the amount of inputs, production proceeds at the lowest possible per unit cost. For these economic efficient consumption situation example, the consumer has much time to wait, the shop has less different styles of products to let them to spend time to choose in the shop's shelf. However, these definitions of efficiency are not exactly equivalent, but all they are caused by the idea that a system is efficient if nothing more than be achieved given the resources available. On time pressure working environment influence aspect, Time pressure working environment may bring efficiency, but time pressure working environment may also bring inefficiency, e.g. employing workers who are not necessary for the productive process. For example, a firm may be more concerned about the political implications of making people redundant than getting rid of surplus workers, or lack of management control, if a firm does not have supervision of workers, then productivity may tall as workers talk it easy, not finding cheapest suppliers, a firm may continue to source raw materials from a high cost supplier rather than look for cheaper raw materials to be supplied to let workers to work in one short time task finishing environment. Then, they may feel short time task finishing pressure to bring inefficiency production result.I shall indicate efficient production and efficient consumption situations as below: For building a new airport working time pressure situation example, how to evaluate that it is one efficient productive situation. When a new airport may lead a greater increase in social benefit than social cost. It seems that an efficient productive situation in time pressure workin environment. The time pressure can excite or encourage workers hard to work and the won't feel pressure to work to cause inefficient performance. Therefore, these is a net gain to society. However, those people living near the new building airport will lost out. Therefore, this is not an improvement. However, if the people living nearby were compensated for extra noise, when the workers need to use equipment build the new airport in the pressure building time when they feel lack of enough equipment supplies or lack of enough workers to cooperate to work. Then, it is possible to have a negative improvement inefficient production. So, how to evaluate whether the new airport builders feel time pressure to finish this new airport building project before the due date or not. It can depend on whether the people living near the new airport often listen noise or not.