What is properly size images?
What Does Properly Size Images Mean? Properly sizing your images means that the image URL should not be larger than the size they are rendered at on the visitor screen. You should not serve anything larger than what's needed – it would waste bytes and make the page slower.
What is a good Google Page Speed score?
A score of 90 or above is considered good. 50 to 89 is a score that needs improvement, and below 50 is considered poor.