Devils Advocate.....
So... I've got hundreds of hours on type.... I'm lying in a field, surrounded by wreckage saying to myself "I could have sworn I'd checked the oil".... the trouble is that memory of repetition/routine means I am recalling checking it the flight before this one but I didn't actually check it today.... luckily I'm still alive because I forgot to check the fuel level as well and there's not enough left to catch fire!!