I got an aluminium incandescent 2xAA flashlight from Poundland that is the worst ever. With batteries installed, the head-twist switch flickered so much when used. After I had finished playing with it, I twisted the head to 'off', or so I thought... Althought the bulb was not lit, there was a short-circuit. Next time I picked the light up, the body was hot, and there was not alot left in the batteries.
I took the head apart to find a shoddy micro-PR based bulb. The switch fell to pieces and could not be put back right. Eventually, I stripped it of the plastic and glass and sent the aluminium off for recycling. That was the first, and only flashlight I have ever thrown out.