Over the past few years I've bought a dozen or so of these things. As of now, I have one (1) that still works(sorta).
The batteries aren't the problem and I don't think it's the bulbs. In every situation, the flashlight turns on and works correctly for a time that seems to vary (long enough to lose the receipt). Then in the middle of a use - it quits! Banging it (gently @ first anyway) with my hand restores the light, then the process repeats.
So far, my experience is with the "aaa" battery types - usually 3 of them in a plastic holder which I suspect may be the culprit (too many contacts to maintain). Also, my experience has been limited to the lower price scales. I admit to being a miser but also have become disillusioned with the entire product line.
I see they now offer LED flashlights that use "C" or even "D" cells with an in-line configuration. Has anyone out there have a good experience with these types?