whats your worst experience with clones?

i recently got some master kush x white widow clones from a dispensary, and after two months of cfl vegging, i moved 'em outside to flower, and wouldn't ya know it, all 3 of 'em were straight up males (not hermies, males). official response from the dispensary: "maybe they got stressed early on." Rrriiiiiiight, sounds logical.
has this happened to anyone else? or maybe a growers negligence affected you some other way (bad bug infestation, mold, viruses), either way please share it, i'd like to know im not the only shmuck with this problem.