Your painting doesn't start when you put down your first brush stroke. It starts when you choose your subject. I live in Pacific Northwest, and it offers some of the most beautiful autumn sceneries in the US. It is very tempting wanting to own the beautiful sceneries for your painting. However, beautiful sceneries are often not the best subject for painting.
I had talked about the suitable subject for watercolor a long time ago. Watercolor is a very different wet medium compares to oil and acrylic, and we need to play on its strength. However, besides picking the subject that's suitable for watercolor, you should also consider a subject that you can make it look more interesting in your painting than a photograph. I made that mistake recently. I took a photo of a beautiful tree filled with yellow leaves and light bleed through. It was a really beautiful scenery, so I attempt to paint it. And as you probably can guess, I wasn't satisfied with the outcome. I do believe it is largely due to my lack of skill to pull the subject off, or my unfamiliarity of this type of subject. However, if I picked a subject that was more suitable for my painting (like the one above), I might have more luck.
Instead of looking for an already beautiful subject and trying to re-capture it into your painting,
look for opportunities.
When choosing a subject to paint, you should look more for potential than how pretty it is. The more beautiful a subject is, the harder it is to do it justice in your painting. A sunlit forest with light and shadows everywhere, a beautiful sunset with the dramatic clouds, or an epic highland scenery. They are all very beautiful sceneries when seeing them in person that will be difficult to capture into painting. Even if the person who sees your painting appreciates it, you might still constantly compare your painting with the original reference and feel the failure.
Look for potential in a reference. I often capture a typical street scenery and interpret it my own way. I do so by rearranging the image, adding elements to it, and recompose the picture. This way, I improve the everyday scenery into something interesting and exciting to look at.
It seems counter-intuitive to pick a seemly boring scenery as your subject and not go for the obvious beauty. However, I think it is artists' responsibility to bring out the beauty from ordinary instead of presenting to people what's already been shown and appreciated.