LUMENS!
I dont know you guys but, a higher high is better than a lower low. I've never ran out of batteries in any aituation, i keep spares in my car, in my house, in everywhere i would possibly need to stay and use my flashlight. So why use a low mode? To keep night vision? you don't need it, you have your flashlight!!!
When there were only maglites, nobody complained about the brightness. Now that we have lighter, brighter, smaller and longer running led lights, some people want very low modes.
I'd prefer to depend on a single bright flashlight and keep some spares, than carrying many lights (one for general, one for low mode and another one for lower low mode) with no spares.