Back in 2012, Google introduces the page layout algorithm. Some users complained that there were too many ads at the top of some web pages (above the fold). Thus, Google has decided to penalize the websites that added too many ads at the top of a page. (reference)
I have read that Matt Cutts had placed two yellow stickies at the top of a letter page (8*11.5) to show that it could trigger a Google penalty. (reference) We don’t know if the stickies were arranged vertically or horizontally but anyways stickies are small.
Anyways, I think this explains why many themes don’t rank well today. Many of them are sold with huge sliders or images between the header and the text. I think it could trigger the above-the-fold google penalty. In 2012, when the
I think that people who add an image after a page title make a big mistake. There are also pages with images like screenshots. I don’t know how Google is able to make the difference between a legit image and something else. I think it is easy to get penalized in this case. Richard Ord from Webpronews mentioned that this algorithm would penalize a whole domain. I already observed a
Anyways it is worth is to reduce the size of the headers and the space between the headers and the title of a page.