Reasons stores and vendors don't honor warranties:
1) the equipment is out of warranty
2) There is too much evidence of a user trying to "fix" the problem (e.g. if they have poked around in the mod guts and etc.
3) User error has caused the mod to fail, and it's visible (e.g.,
tanks overtightened or screwed together to tightly, leaking down through the mod and or other evidence of improper use
4) They suck as a company as far as warranties or customers service (sadly, a new vaper, and I went through the process with ONE vendor, whose Terms of Service I would have found completely unacceptable, HAD I READ THEM, so I consider the fault my own, although I will never patronize that company again, either.)
5) The warranty period is from date of purchase, but your mod takes a month to arrive to your location and it eats into the warranty.
HOWEVER: I think you have a more specific question than that. What did you try to warranty and how did it fail? As, you'd probably want to know
why your warranties are "sucking" and it could be from any (and more than one) of the above reasons. There are probably also other reasons that I am an unaware of.
Anna