That reminds me. I bought two used 827 13w PL-S lamps. A Philips and a Sylvania. The Philips one was made in Poland and the Sylvania was made in China. Both had blackening that looked the same. I put both into use in two separate fittings and the Sylvania died after one month! The Philips is still going strong after nearly four months and the blackening hasn't changed!
Were those two lights run at the same rate or they were used more for one fixture and less for the other one? How often were they switched plays a part. If they both were in one fitting and Sylvania dies before Philips one, you might have a point. Since they were in separate fittings then there’s too many variables at play to make it a valid experiment. Hence the questions.
Sadly, manufacturing quality goods in the first place is not at the top of most companies' agendas these days. Planned obsolescence means they make as poor a quality item as they can get away with, to force consumers to buy new ones of whatever it is every few years (or sometimes even months)
Take television sets, for example. Years ago there was a whole cottage industry dedicated to repairing items like this; if your TV stopped working, you could take it to a little back-street shop where a man in a brown coat would open it up and replace whatever component had failed. Now it's a case of just throwing it away and buying a new one. I don't know about other people, but I can't afford to spend several hundred (or even thousand) pounds on a new TV every four or five years
Have you ever seen inside a modern TV? Lots of tiny components and connectors which can break easily if so much looked at wrong. I don’t blame manufacturers for the newer TVs being hard to fix making them throwaway stuff. I blame the consumers thinking the thinner it is the modern and top tier it is. An 8K TV can be made with larger components and connectors making the whole case 3” or 4” thick instead of 1” or less they are these days. But no, people wants thin TVs because they think it’s better quality or whatever.
Planned obsolescence? More like it just got harder to fix things. Harder means more costly meaning it’s cheaper to toss it.