Inventing is difficult, because in many cases if there was a need for it, it would very likely already exist. However, with improvement you can take what is already needed, and increase the need by making it easier to use, or by making it more powerful.

For instance, when the internet was invented, they spent 20 or 30 years convincing people they needed it with very little improvement along the way.

However, once people recognized that they needed the internet, the influx of improvements over the last 15 years has increased by 100 fold, if not by an unmeasurable much larger amount.

Need drives improvement. Invention simply creates the opportunity for need.

This is why many inventions have been tossed aside while improvements things we actually care about are constantly being made.