[M]ore than 1,000 fans [were] turned away from turnstiles for up to 1-1/2 hours over a bizarre ticket snafu.|The fans – many of them season ticket holders – were forced to wait on line until as late as the fourth inning to get replacement tickets after accidentally tearing their ducats out of ticket books without the stubs.
—Stuck at the Gate  (NY Daily News)

Blame the user — a typical management ploy. I haven’t seen a picture of the tickets in question, but if 1,000 people all made the same mistake, the ticket books were poorly designed. Period. Usability testing could have caught that long before it angered so many people.