Science is constant exploration and continually asking questions. One experiment or discovery does not close the book on a subject but merely gives a nod to which direction to next pursue. A true scientist never will say that he/she knows everything for they know too well that they do not.
I have grown plants for a very long time and I will never have all of the answers. Plants constantly amaze me and that is why, after all these years, I am still in the hobby. I am constantly learning something new about plants and constantly being fascinated by them. Why would I waste my time on a hobby that was boring?
Growing a diverse group of plants is a great way to be forced to learn about other climates, countries and, in some cases, history (depending on the plant).
When I first began growing orchids, I never realized how diverse they were. I knew about the more common ones but...wow. And, with the other plants, I never cared about their scientific names. It was good enough to know them by their common names. Growing orchids make me pay a little more attention to the scientific names of the other plants that I grow.