Stock images exist in articles. A stock image exists at the top of each article, below a title or above it. The image can also exist on every section, below every sub-heading. The purpose of stock images is to make the article look better supposedly. But it is not. In fact, those stock images make your website look ugly and generic and blend with the crowd.
Stock images make your website ugly. If you choose stock images that have nothing to do with the article, you already make your website ugly. Those images add nothing. They are just annoying images. They also give you a negative impression. When I read an article with stock images at DEV Community, I often ask myself, "Why do these people put useless images? Why do they want to waste my cellular data? Why do they want to waste my time?" Those authors are weird.
Stock images have nothing to do with the content. To know that, we ignore the images and see if we miss something. When we understand the content without those images, they are decorative images. They are not really "decorative" because they are part of the article. But they are also decorative because the purpose is to make the article look interesting. At least, those are what the author thinks. For me, those images do not add beauty to the website. They make your articles look generic. They are not your content, and they do not make your readers content either.
Stock images make your website look the same as others. They have been overused. If you often see an image showing a laptop, ask yourself, "Why does the laptop matter?" The laptop is not yours. It is just a stupid laptop. Even if the title says something about programming, still the content is not about the laptop in the image. I think the laptop is much more popular than the owner.
Stock images look fake and inauthentic. Seeing a fake smile does not make me smile.
Searching for stock images is a waste of time and energy. Those people probably have more time than the rest of us. They are willing to spend their time on something that their readers do not need. That is a sign of intelligence.
Stock images have potential legal issues. Some are copyrighted images. You do need to be careful if you want to use one. Pay attention to the license. Read it. If you can not find it, do not use the image. Complicated? Then, do not use stock images.
Simply, I say this to you: please do not make your article like a comic.