Why is the power factor of a fully loaded 3-phase induction motor not very high?

A 3-phase induction motor draws a large magnetizing current because of high reluctance of the magnetic circuit; air-gap being the main reason. As load is added, the active component of current increases, resulting in higher power factor. However,because of the large value of magnetizing current, which is present regardless of load, the p.f. of 3-phase induction motor even at full-load seldom exceeds 0.85.