The sunsets everyday! Only to rise the very next day ! All that starts has to end ! And al that ends starts again ?
Essentially, a nincompoop is a fool, a stupid person whose incompetence or naïveté is quite apparent. It is often used to describe people of a much lower social ranking, although some may describe an unpopular or incompetent leader as an "utter nincompoop." It is conceivable that the originator of "nincompoop" was seeking to combine several unsophisticated words into one nonsensical but descriptive word.