When I was in dentistry, I loved continuing education. After decades of attending classes, and being named a Fellow in the Academy of General Dentistry, I still took weeks out of my practice each and every year to attend classes. I always told my wife that if I came home with just one idea, an idea that would make me a better or more knowledgeable dentist, the days of classes and training would be worth it.
Of course, those days are gone. Now, I've kind of reversed that philosophy. When I have visitors, and that's pretty frequent now, I tell myself: "If I can impart just a single bit of information, information that increases my visitor's knowledge or improves their technique growing and/or propagating tropical plants, the visit was worthwhile". I don't care whether I sell anything. I grow plants and propagate plants just for the shear delight of doing so.