One trap that I fall into is “why would anyone need that.” Even though the need might not exist, it may in the future.
BTW, I remember the hype around the Segway and it wasn't that popular. Probably mostly a marketing ploy to drive interest.
Thomas Edison, during his quest for the electric lightbulb, ‘discovered’ a phenomena of heated elements in a vacuum that caused a cloud of electrons to be emitted and if a positive charged piece of metal was placed near it would cause a current to flow. This became known as the ‘Edison Effect’. He did not see any use for it at the time, and so forgot about it in the course of his experiments.
This ‘effect’ eventually became the basis for what would become Vacuum Tubes or Radio Tubes..........................