Primary reason you see good products change is to keep sales moving. If everybody buys a light bulb, it works great, never breaks... GE wouldn't be in business after a few years (much less giving top dogs million dollar bonus's!). Soon everyone would have all they need and your unable to move enough product to keep your doors open for business.
Now if you can make some little trendy change to the product and call it "new and improved"... NOBODY want's "yesterday's", "old style" light bulb!!!
$$$ CHA CHING! $$$I was in sales for four years, it taught me a LOT about how American works, and why we're the biggest "consumers" in the world market.