The first watch out in understanding a chart is looking at the scales. These can be easily distorted to misrepresent findings.
Take a chart that is a portrait and make it landscape and it instantly stretches out.
So do compare the scales, and the metrics used on each axis.
Then explore the data itself, how was it collected, how many data points are in here. Can you draw or add any trendiness? Is the data substantial enough to support conclusions?
Don’t simply take a chart at face value, go that bit deeper to understand it.