“We used to recommend adding an image to every article. Now we recommend adding an image to every scroll depth of every article. So there is never a point at which the visitor doesn’t see something of visual interest.
And what’s the secret to high dwell time? Content that engages the visitor quickly and keeps their attention. That means no long blocky paragraphs and lots of compelling visuals.”
Crestodina, Andy. June 2019. How Images Affect SEO: Can Adding a Diagram Really Drive Rankings?