Why do Seyfert Galaxies strengthen the case for quasars being active young galaxies?

Question

Quizplus · Accepted Answer

Seyfert galaxies, which are closer than most quasars and less bright, serve as a sort of intermediate class of active galaxies. Their properties suggest that quasars, which are more distant and more luminous, could be an earlier, more active phase of galaxies like Seyferts. This supports the idea that quasars are active young galaxies, with Seyfert galaxies possibly representing a later, less active stage in the evolution of galactic nuclei.

Why Do Seyfert Galaxies Strengthen the Case for Quasars Being