The general trends of rapid beginning continues for some time after it slows down and reaches a level where no further improvement occurs. The learning curve travels in almost a horizontal plane. These horizontal stretches indicative of no apparent progress are called plateau.
Causes of Plateau
(1) Boredom - Some routine work often brings boredom, it is one of the cause of boredom
(2) Lack of Practice - Lack of practice often causes plateau and stagnated performance
(3) Dirty environment - Poor, dirty and unsafe environment may cause plateau.
(4) Lack of Motivation - Lack of Motivation and less feedback often causes long learning plateau.