Imagine you're on a walk, you see a tree, you particularly like how the light fall on it, so you take a photo. Coming back, you see that tree again, the light has change, and you also particularly like how it falls on it, so again you take the photo. Doing that, you are no longer photographing a moment in time, but the passage of time, and how it has many ways to transform us. That is your intent, so you include both photos in your book, as there is no "best" of the two.
You could even imagine yourself just sitting in front of that tree one day, from dawn to dusk, and photographing it every hour, or every half hour, or every time the light changes in a way that speaks to you — it would be the same tree yet never the same —, and then making an entire book only of these photos. (Since I made the suggestion, of course I'd have no choice but to buy it !

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Having two of the same, yet different, is a great way to draw the viewer in. Viewer has no choice but to stop and look, even if just for differences, not only in the surface of the photo itself, but also in feeling. Viewer becomes more attentive, and that attention is then kept on single images.
I may be wrong — memory fails me — but I think Italian photographer Luigi Ghirri did this a lot.