Well, how do you decide what kind of colours and tones you are after? For example post #968, which I can't stop drooling over, did you have an original goal as to how you wanted it to look when importing into Lr? Or does a quality lens add a lot to the overall tones from the get-go?
It's difficult phrasing it correctly enough, but when I import my images into Lr they just look really flat and unsharp. I guess it's to be expected since it's only a kit lens, but when processing an image I'm not sure where I want to go with it. That's why I usually do B&W photos, I feel I can sort of dodge the difficulty that is colouring and tones/levels. I guess most of this is by experience as you mentioned.