Gold as a dental material has multiple benefits: It is malleable , inert , and can be placed in areas where there
is relatively little space (as opposed to porcelain or resin , which generally requires a greater thickness to withstand the biting forces) . The dentist may have been reluctant to grind the gold crown , fearing that grinding
would create a hole in it (by thinning it too much). Dentists often work with millimeter calipers to
help them measure thickness of materials to avoid this issue. Alternatively,the dentist may have adjusted adjacent or opposing teeth because he/she noticed interferences that needed to be removed.
I hope this helped answer your question. I urge you to discuss with your dentist in an open manner. This will facilitate understanding between you and your dentist . With open communication, results and trust improve. And I am quite sure
the second time will be a charm!