I have a mate wot his wife went to the Army one. It was all she'd dreamed of since being a little gurl. She'd studdied and swotted for it and when she gets there they give her an exersize to get over an electric fence with a couple of planks, a Fairy Liquid bottle and some lollipop sticks.
No slouch her, she'd been watching Blue Peter, so she lays the plank onto the fence and gets her team over wivout a scratch on 'em...good as gold it was definately one in the bank she thought...only to be told she's failed.
"Wot?" says she "Wot d'yer mean failed yer tw@t?" the last bit under her breath of course.
"Well you got electrocuted because the plank toucheth the fence" came the earnest reply
"Bollocks!" quote she in a dudgeoness voice "wood doesn't conduct electricity you pig higgerent product of a council estate." again using sotto voce.
Well a kindly soul took her aside and said "Look luv they're doing you a favour here. You're right of course, any moron can tell that, but if you get upset at this show of ignorance, believe me, being in the Army will be like hell for you."
So instead she became "something in the City" and made packets and packets of money.