I'll explain.
Sometimes, I see a website which contains an image containing text. Often, the image has been carefully chosen and the text well-written. It may be the "hero image" i.e. the main image at the top of the homepage. The text within the image is the main message that the website owner wants to convey. It contains the key words that they want Google to find.
But, here's the kicker, Google can't read it!
This is what happens. The business owner spends ages refining their product and identifying their ideal client. They research key words and consider what their potential clients will search for. Then they craft their key message including vital key words into a succinct and clear description of what they offer.
So far, so good.
But now comes the big mistake.
To make it look pretty, they go onto Canva, or some other graphic design tool, and superimpose their key message onto a lovely, aspirational photo. (Don’t get me started on aspirational but meaningless photos on websites. That’ll be for another day.)
And now they download it and pop it on the website.
It looks gorgeous.
But all Google sees is an image file.
The text they spent so long crafting is now just part of the image. Humans can read it but Google can no more read the message than it can appreciate the beauty of the mountain range on the photo.
So, what’s the solution?
Keep text as text. Google can read text.
If you want text on top of an image, add your image to your website, then add a text box on top.
Your human readers can still read the text but now so can Google!
Bonus tip 1 The same applies to using graphics containing text on your social media posts. Social media algorithms can‘t read text inside images either. If the words are important, make sure you use them in the text part of the post.
Bonus tip 2 Don’t forget to add alt text to your images. Google can read alt text and, importantly, it helps make your website accessible.