Weird phenomenon with Quark 123^2 high CRI

On Christmas eve I was out on my usual overnight trekking trip and had my high CRI Quark 123^2 with me. The Quark was functioning perfectly and I was still shining it around when all of a sudden it died. My first thought is that the batteries had exhausted themselves, but it doesn't seem right since I was still using the original batteries from 4Sevens and AFAIK primary batteries don't just cut off suddenly without at least dimming down or flickering to show that it is weak.

Anyway, I changed out the batteries and it still doesn't work. So my friend did a swap with his body tube and tail cap and still no light. Finally after trying different combinations and configurations using all the other Quark available on hand I came to a conclusion that the electronic in the head is the cause of the problem.

Last night when I got home I decided to clean out the contacts and try it one more time to see if it work. Still no luck. Today I thought I would write in to 4Sevens, and just when I completed writing that email I thought I should double check it again before pressing the SEND button and guess what? It worked flawlessly!

What exactly is the problem then that causes it not to work for an entire 24 hours when I needed it most? I couldn't seem to figure it out. Any guru around here who may know?

EDIT to add: during those times when it refuses to work, it still emits a very short and weak light whenever I click the button on. More like a short blip and no more.

I don't know much about flashlights, but could it have been moisture?

That could be one reason since it was flooding from the sea that very night and I was inspecting the damage caused by the flood in one of the villager's house but the Quark wasn't even submerged. There was a slight drizzle though but I doubt a drizzle could cause any problems since Quarks are IPX8 rated.