If a dimension line loses its association (history) to the object it is dimensioning, many cases exist when the “drawing” will be wrong (geometry changed, dimension lines still shows the old values). In architecture drawings are unfortunately still the most important tool to communicating dimensions, due to the manual / human based construction work. Wrong dimension lines cause serious legal trouble. With hundreds of dimension lines in a project, it is very labor intensive and error prone to check them all after a change.
Please see this older post, for a suggestion on how a useful warning dialogue box could look like: Dimensions features