Here is a list of good questions to ask when making a statistical map or thematic map, following the WHO WHAT WHEN WHERE WHY and HOW pattern:
Who is included in the target audience for this map?
Who provided the data shown on the map?
What should this map show?
What does the popup show to illuminate the subject?
What is the first thing you want the reader to understand when they see this map?
What question(s) does this map answer when the reader looks at or touches the map?
Is there a time period that the map's data represents?
When will you share this map?
When will you expire this map?
When will this map be updated?
Where is the most interesting part of the map? Is that set as the default zoom level?
Which map scales capture the "sweet spot" of this map's story?
Why are you making this map? To share raw data? To share your analysis results? To make analysis possible?
Why will this map work?
Why should the reader care about this map? Did you make them dig for that, or is it evident in the choice of colors, classification, words, and popup content?
How can a reader contact you with questions?
How was the data collected or created?
How can a reader use this for analysis? Visual? Correlation? Causation? Proximity? Hot spot? Normal/abnormal?