I made a arcade game once: www.abril.com.br/blog/campus-party/2011/01/19/fanatico-por-jogos-leva-seu-proprio-fliperama-para-a-arena/
It has instructions printed on the sides of the screen... It was VERY, VERY, VERY common to someone ask people around them what a button do (sometimes to even random passerby people, or for example a couple arrived at the machine, and the guy would start to play and ask stuff to his girlfriend), and then the asked either looked confused, or pointed to the instructions, and the people asking would behave surprised, confused and shamed.
Why people ignored the instructions and asked for example their girlfriends, random people and so on instead?
Why people see a huge sign blocking the way to a ATM saying it is out of order, they remove the sign from the way and attempt to use it anyway?