one bite short of an apple 

The term used to describe an individual or group of individuals who display a certain degree of insanity by making up excuses that are implausible to the extreme in a feeble attempt to deny responsibility for their mistakes.

Boss: "What time do you call this, your 6 hours late."

Employee: "I'm really sorry I'm late sir I was err.. abducted by aliens, on my way way in. They returned me to earth in the middle of a field and the nearest train station was twenty miles away. I definitely didn't spend last night clubbing and get up 6 hours late."

Boss: "Who do you think you are kidding? You must be one bite short of an apple if you think there's any hope of me believing that!"

or

Fictitious mobile phone manufacturer: "Our phones appear to have poor reception when held because our stupid customers are hold them the wrong way. The 'signal strength formula' feels intimidated by humans and gets it's maths wrong whenever it is in the centre of a fist. This makes the poor innocent little formula accidentally display the wrong number of bars. The call quality appearing to drop is purely coincidental, as is us releasing an insulation cover and recruiting eight new antenna engineers. There is definitely no design floor. Even if there was, it is definitely nothing to do with the very sensitive revolutionary external uninsulated antenna. The antenna is just being ridiculed for being pure genius, by people without any imagination. All you have to do is imagine it works perfectly and you won't find a single fault. This worked just fine for us during testing."

Anyone with at least half a braincell: "They really must be one bite short of an apple if they think anyone is going to believe any of that!"

one bite short of an apple by iCantMakeCalls July 7, 2010