(e) Levelling All learning will finally slowdown to such an extent that it will ultimately reach a period of no improvement. No one can continue to improve indefinitely in any given situation. The learning curve will eventually reach a limit, where no further improvement is possible. This limit is known as physiological limit. 4.5.1 Characteristics of Learning Curve. (i) Slow initial progress. ii) Spurt-like learning after sometime. iii) Declination in the rate of learning. iv) Plateaus of learning. v) Sudden increase in learning. vi) Gradual levelling at the end.