You can find that by searching on just about any author who's been around for over ten years.
Why do authors and publishing houses change their covers?
For one thing, what a cover image "means" to people changes over time. For example, in the 1960s a romance novel might have a cover with a quiet cottage with roses. To those readers, the cover signified romance. In the 1970s, a romance novel might have a lovely woman staring out into a sunset. Again, those readers had a connection with that image. In modern times, audiences tend to expect a romance cover to have a man and a woman together. If they saw that cottage-with-roses they might think it was a literary fiction about a grandmother mulling her life. An image of a single woman might be a tale of one woman's journey through life.
Also, even the use of certain colors can add a modern or a dated feel. In the 1970s covers were often done in a faded style with oranges and greens. Those colors were popular back then. Illustrations were often not of the highest quality. In comparison, our modern world of high-quality photography means that even unknown authors have access to amazing images. The expectation of a modern cover is that it'll have top-notch, well-lit photography showcasing something to do with the topic at hand.
I'll give a variety of examples of the changes my own covers have gone through over the years. It wasn't always easy for me to "let go" of my original cover. In many cases I was absolutely in love with my first cover. I adored it. But it just wasn't connecting with my target audience. As I updated and tweaked my cover, the sales and good reviews poured in. It's well worth it to look at updating that cover every year or two - even with minor changes - to further hone in on that audience.
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