Parkinson's Law of Triviality / Bikeshedding
What is bikeshedding?
Members of an organization give disproportionate weight to trivial issues.
Parkinson provides the example of a fictional committee whose job was to approve the plans for a nuclear power plant spending the majority of its time on discussions about relatively minor but easy-to-grasp issues, such as what materials to use for the staff bike shed, while neglecting the proposed design of the plant itself, which is far more important and a far more difficult and complex task.
How to overcome the bikeshedding?
Having a clear agenda of the meeting. Or even do not mix complex topics with easy ones.