The problem is that nobody checked lumen/watt, or had the knowledge to make an educated choice based on it. Imagine you sold a 2000 hr bulb that has two filame

The problem is that nobody checked lumen/watt, or had the knowledge to make an educated choice based on it. Imagine you sold a 2000 hr bulb that has two filaments in it, in parallel. It would fit the same fixture and make the same light as the equivalent 1000 hr bulb, but it would consume more because it runs at lower current and temperature. You would make more money: almost all of the cost is the same as for the 1-filament version, but you could sell it for a higher price because it lasts twice as long. The buyer would pay for it slowly in the electricity bill, and ultimately be screwed.