Top 10 reasons to create Top 10 lists

Two of the top three reasons are because lists require little thinking effort by the reader and they give the impression of credibility. The average reader rarely challenges the automatic authority granted something labelled "Top 10 Whatevers," so they are easy to put together and astonishingly well-read, providing conversational fodder for the water cooler/grande latte crowd.

Reduce the complexities and nuances of life to lists and bullet points and you have a winner. Caveat lector.