I've been reading Guy Tal again. I dip into his book More than a Rock on occasion and yesterday came across his thoughts on Projects. What he said resonated in that he doesn't call them Projects, he considers them Explorations. Projects indicate a completion is somewhere in the (hopefully near) future. Explorations continue for as long as the artist feels the need to explore a subject, approach or idea. Once that theme is absorbed to its fullest (or boredom sets in) the exploring ends and ideally a new one begins. It fits the thematic approach for what I was previously calling projects.
From Hollenbeck, Simply