Loss of battery life for no reason?

Hi, I'm new here but have an age-old problem.
Why is it that some lights (e.g. from B+M with brand new normal (non-rechargeable batteries) will last for at least 2-3 years under normal, restrained use, but a light from CatEye with the same type of battery and use will cough out after even a few months? I've not yet been able to find any bad wiring or debris or something like that and I've long since tested and retested both with new batteries, recording when and where and what type etc.
Thanks for any suggestions. Or is it just a question of "brand quality"?

Mike

All lights with electronic switches got paracitic drain. (they draw current when off because the driver is in "standbymode" waiting for impulses from the switch) They operate the same way as your computer when it's in sleepmode. It draws current, just waiting for you to click that mouse to wake up. Some lights use more current than other lights in this "stanbymode". Lights with mecanical switches totally cuts the criut, so no current is drawn from the batteries when off. Take the computer again, if you unplug the cord to cut the criut, it cant draw current.

When you store the light, try unscrewing either the Tail or head to break contact. Test by turning on the light, then unscrewing. If the after a little twist, the light goes off, then you are good to store it. I usually twist it back tight, then turn it off, then twist it loose to break the connection. Not all lights will allow this type of "Mechanical Lockout", but many will. This is especially helpful for lights that have multiple cells the will be stored for a long time.

Thanks, guys! I was afraid of that and I have used that as a "last resource" e.g. in my Nitecore EA4 Pioneer. But I do find it a pain in the ahh, y'know to have to do that all the time, just because I don't use it everyday. But I also have a few other lights like from LedLenser, Walther, Olight, and Litexpress which never show that problem. BTW, yes, I have tried to keep my Nitecore in the "Lockout" position when not using it. And those other lights don't even have a "Lockout" mode (I think).

Mike

Hey moon, just to be clear. Typically there are two ways to lock out lights. One is electronic through the User Interface, the other is physically by breaking the circuit. Some lights you can't do either, some can do just one, some can do both.
Electrical lock out: is sorta a new thing. It usually entails some sort of button sequencing. For example: pressing and holding the ON button for 10 seconds, then three long presses to turn the light back on.
Physical: Some were designed on purpose to be able to physically lock out, some just happened to be made that way with the lock out as a added bonus the designer didn't actually plan for.

Well, thanks... that was fast. I believe you and will now confess that it's of course not just the light's "fault". I should check better those properties out first and then do what the light will allow (or need). Still, I do find some brands' construction a bit more logical and/or "comfortable than others'. Thanks, again.

Another way of thinking bout it. Lights or electronics with electrical switches, and not mechanical switches are basically always on "stand by" waiting on your input. That standby has a normally small, but measurable current draw (aka parasitic drain). Depending on the light, and battery this tiny draw can deplete a battery rapidly.
To go a step further down Ponder Road: some lights also have a voltage cut off that will not allow the light to work if the battery voltage is too high or low. So theoretically speaking, a light that has a moderate amount of current drain on standby, loaded with a weak or inferior battery, that has a "high" low cut off voltage may appear to some people to be terrible at killing a battery when not in use. Even though you could put this same battery in a different light and have it work seemingly fine. Does my rambling make sense? Overkill? lol

FWIW: The some of the worst lights I have found for Parasitic drain are Nitecore. Mind you, I am aware of it, they are aware of it, so some of their lights are designed to combat this. But it does require user education and common sense. The HC90 headlamp, one of my all time favs seems to be one of the worst offenders. It will KILL a very high quality battery in less than a week! BUT..........It has a very easy to use mechanical lock out. Just unscrew the battery cap a tad, an you are good. The Explorer series is another. They have both Electrical lock out and physical capabilities. Both work well, but I have trained myself to physically lock out lights. Yup, dummy me destroyed TWO Efest batteries with that HC90 not paying attention with them.

When you have a collection that numbers in the 100's of lights, you begin to learn to lock out, or remove batteries. Oh and Don't get me started on alkaline cells. I have cut small pieces of plastic (usually bike tire patches) that I put between the cell and the tail caps for storage. That way if I need the light, just unscrew and remove rubber. Pain in the butt? No not really. Most of those are mag lights and are for back up to the back ups, for the back up of the back ups. Really, they are loaner lights. lol

Crass! You are so helpful!! I'll buy that about the patchwork. E.g. I can save the thin soft (yellow) plastic patch which came with the S30R III I got yesterday (the type of thing that usually comes with any light or stop watch e.g. for the kitchen) and just put that back in where it came from, screw the tail on and that's it. I'll now do that for my EA4 Pioneer. Boy, that'll help for sure. I'll tell my EA4 that you sent me!