I have not worked for a medical device company . But i worked for a drug company for 2 years. Scope creep can occur, in my case we had to start all over again. We used to make Morphine control drug. It was a new drug that we started. We did our verification and validation and submitted to FDA. Planning and execution phase all went well. And FDA approved our submission. Production line started producing in buck. When we started to sell that product. We were not able sell the drug as expected. It was because the drug was bitter due to the control substance. We arranged a meeting how to resolved this issue. we came with a coating material that will prevent this bitter taste. It took us almost two years to resolve this issue and bring it back on production.