Remember a few years ago when flashlights had no fixed, defined, objective standard for brightness, distance, or even how long the light would last before the batteries croaked?
Ads for those D-cell flashlights would say, "Super Bright!" "Max Brightness!" "One-Mile Range!" "Best Performance!" and of course, "Long-Lasting!"
This is the problem of a lack of objective, measurable standards. Without them, we are reduced to subjective opinion. And opinion is subject to bias and self-interest. "In my opinion, the light from this flashlight is indeed Super Bright." And, "In my opinion, my flashlight has the best performance."
[Interruption for advertising clarification. In real life, "best" is a claim of superiority. "I am the best!" But in the bizarre world of advertising, "best" is a parity claim. All marketers can claim their product is the best. And so everyone is the best and all are equal. Just don't claim your product is "better" unless you have tons of evidence because "better" is a superiority claim in the advertising world.]
So LED flashlights arrive and the wild claims continue. A few marketers start using "candlepower" which varies depending on how it is measured (how far from the bulb, for example). But still open to subjective manipulation. In other words, my 20,000 candlepower flashlight might be brighter or dimmer than your 20,000 candlepower flashlight.
Enter the ANSI (American National Standards Institute) FL-1 standard, which measures flashlight output in lumens according to a fixed protocol.
Yesterday, I just happened to be flashlight shopping and noticed the variety of light output. There were flashlights rated from 9 lumens (a traditional 2-D-cell flashlight, through 64, 120, 200, 700 and so on. Of course, the 9-lumen light was only $2.49 while the 700-lumen light was $39.99, but you now can make an informed choice.
[Last caution. If you shop on the Web, be careful because lots of ads will claim huge lumen outputs for very low cash. They might not be measuring by the FL-1 standard.]
Philosophical conclusion: Fixed standards, like fixed values (hint: Ten Commandments) make decision making much easier--and with more reliable results.