I'm typing a document with what I will probably turn into actual headings eventually, but for now, I'm just typing them in boldface without designating them as headings. Word concludes they are are headings anyway, so puts them into the Document Map. However, it's not always accurate in what it concludes is a heading. For example, it placed the first line after one of the headings into the Document Map even though nothing seems to distinguish that first line from the first lines after many other headings (e.g. presence or absence of a pilcrow).



Interestingly, when I un-bold one of the headings, it remains in the Document Map.

-> On this occasion, only one non-heading was promoted by Word in this way, but on other occasions Word's decisions in this regard, and their seemingly random nature, have been a lot worse.