Especially selling pens as forever items means you put a lifetime guarantee on them, how can anyone predict how customers will treat them. Forever ago I bought a vacuum cleaner for 1500 dollars thinking with a lifetime guarantee for our home it would be wonderful.
Actually it failed, I contacted the dealer who said just as well I had the two yr warantee expiry date was the next day.
Plating, blanks be they timber or plastic are all subject to failure and misuse. A minefield IMHO.
Peter.