It started with a simple question: "Can we get as built drawings?"
It ended in a musty basement facing a huge pile of yellowing prints. There were literally hundreds, most torn, tattered, and largely forgotten.
They were drawn with a pen in an artful way CAD can't. However the thought of documenting a large project this way made me cringe. A single change would have impacted dozens, maybe hundreds, of sheets but it's not the only reason to love BIM.
That heap of prints was the owners record of their building. It's the reason Owners need BIM, a digital reference, long after the design is finished.