I can look at one of my images and know approximately when I processed it based on how it looks.
Obviously, if it's color, it was a while ago, since I stopped using color for my art prints many years ago. But even the black and whites have a distinctive look depending on how old they are.
I've always liked deep, inky blacks. I know there is a trend toward low contrast, washed-out photography, but that's a fad that will eventually run its course. I tend to avoid doing the same thing as everyone else, not in spite of the fact that it's popular, but maybe because of it.
My concert photos are always processed with a strong grain structure. I want them to look like they were shot with an old press camera in extremely poor conditions using very high speed film. (In truth, they are almost always made in low, changing light, with a moving subject that sweeps into and out of focus, so ... challenging.)
My portraits are usually softer, but retain some grain structure to take the edge off the overly-sharp digital original.
I want my landscapes to be incredibly sharp and deep, with details that jump off the print.
And yet, as I look back at older prints, I can see clearly how I've changed and evolved into what I think is a personal style unlike any other.
Ansel Adams likened the negative to a musical score, while the prints are the performance. While the score never changes, a conductor and orchestra can render the sounds of the music in ways that no one has ever heard before, or may never hear again. Digital photography workflows mean I can print again and again with exact precision, but the way I process each image changes every time I do it.