Spanish> I think you're asking more along the lines of what happens when someone DOESN'T check straight away and shite happens down the track - 12 or so months later?
Bad luck. I'd say! If someone was to buy one of my bikes (should I ever sell one!), I know it'd be fine for a while, but I have heard of people doing as you suggest and look for some sort of comeback later down the line, after racing them for 12 months or more. Personally, if someone was to look for some sort of recompense with me, it'd want to be damned early in the piece or they'd be not getting a hearing!