This process is only partly conscious. I think of these as like footnotes. It is patently fraudulent to have a paper that is mainly footnotes, and I think the same about paintings. Footnotes are OK if they add a little optional, supporting elaboration, but they are mainly negligible, not a substitute for real content in the main body of a work. A work of art must stand on its own.
Objects are never there as proxies for some symbolic idea.
They are there because I like the way they look, and they fit the visual theme of the painting. A natural world, of distinct, definite objects, each of a specific nature and obeying natural laws. The objects are only part of the picture. More of the theme is achieved by the composition and rendering, and here there is not only the matter of unifying and contrasting shapes and textures, but also the contrasts of empty and full spaces, the paths I lead your eye in, and the careful modulation of edges, with some of them very sharp and others very diffused. I think selective focus is very important.