Cyril Northcote Parkinson, a historian and author, formulated this observation about the human tendency to devote a great deal of time to unimportant details while crucial matters go unattended.
Parkinson observed a citizen committee organized to approve plans for a nuclear power plant. He noted the group tendency to be silent when focused on technical matters such as the design of the nuclear plant, but when it came to the design of the bike shed, everyone had an opinion. Because people are often ill-equipped to consider complicated subjects, they tend to focus on trivial matters.
Thus the act of wasting time on trivial details while important matters are inadequately attended is known as bikeshedding.
Parkinson is also known for formulating another principle known as Parkinson’s law – that work expands to use up the amount of time allocated for it