” implying brands have a finite life and cannot be expected to be leaders forever.

Often, after a brand begins to slip in the marketplace or disappears altogether, commentators observe, “All brands have their day,” implying brands have a finite life and cannot be expected to be leaders forever. Other experts contend brands can live forever, and that their long-term success depends on marketers’ skill and insight.
Take a position: Brands cannot be expected to last forever versus there is no reason for a brand to ever become obsolete.