It would be helpful to know if the pump is submersible or is a jet pump. But generally speaking, those motors can be run continuously. Pumps that are not intended for water wells may have lesser duty cycles.

A well pump used as it's desighned for can run non-stop without ill effect. The most common problem resulting from long run times is pumping the well dry. Why would they run nonstop if given the choice to?

Your well friend may be treating the symptom instead of curing the disease by shocking the well.

I've seen more well pumps killed from introducing chlorine down the well than exceeding their duty cycles.