Some guesses on my part-
Maybe your tendency towards precision is at the wrong times? If practicing, for example, it might be counterproductive since you probably want quantity instead of quality, or maybe you're trying to get everything down precisely too early on and it's making your work stiff.
Manfred's point is good- "metaphor that captures the scene without the need for detail."... If you render background details overmuch, they can distract the viewer from the focal point of the work. Maybe put some effort into looking at how the "m