There are very few businesses that last forever. Most have some kind of a bell curve, from a ramp up to a peak and then a decline. How a business survives and keeps growing is the preoccupation of most, but it can become a nightmare for a business whose model has run its course.
For example, take 8-track tape:
8-track had a very brief moment of popularity before being eclipsed by the cassette. If you were in the 8-track business, at some point you were faced with the reality that the sun was setting -- and setting fast!