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Look for boxes that have both Red and Green in them. This means the same time slot is the best performing one for one of the statistics you are comparing it with, and low performing for another. 

For example, if a campaign is getting a lot of clicks in a certain time slot but does not have any conversions, you can schedule that campaign not to run at that time by using ad scheduling in Google Ads. This will make sure that the campaign budget is spent better during time slots that convert better.

Identify time slots during which conversions are high, and impression share is low, and increase bids for these time slots.

Account-level statistics may not be accurate indicators of performance as, for example, mobile may perform better at night compared to desktops. You can change these settings from the menu on the left side of the page.

We suggest you review data for a longer period (45 - 60 days) to make sure it is statistically significant.