Never ending, that is the term for developing taxonomy. As time goes by, new setup take in place which lead to new requirement or reorganizing the taxonomy. It is unavoidable and understandable. But what if because of other department or other fraternity understands it differently, you required to change your taxonomy setup? Definitely NO!
Taxonomy definition during development usually takes consideration of consumer and creator of related contents and properly apply relevant metadata on top of it. Applied metadata might consist of, department names, discipline names, phases, project name, processes, and any other key attributes. Give an example from main taxonomy it do have finance related content in multiple nodes. From finance department point of view they were only interested to finance related contents, thus by constructing another facet from main taxonomy’s metadata, department type taxonomy can be display.
Another example is some of the taxonomy nodes can be re-grouping on another facet. Development and operation’s activity can be group under technical’s view. Same goes to managed services should fall under support were taken out to be the parent of support. It is something similar of reversing the arrangement.
By constructing taxonomy through multifacet taxonomy definitely will help when dealing with predefined work breakdown structures. The most important part is to properly manages and assigns metadata to it relevant contents.