Murphy bought himself a chainsaw which according to the salesman in the shop was guaranteed to cut down 30 trees in an hour.
Murphy started using it, but he was barely managing to cut down 10 trees an hour.
Frustrated with his new chainsaw, he took it back to the shop.
He said to the shop assistant, “This chainsaw doesn’t cut 30 trees an hour, I’ve only managed to cut 10!”
So, the shop assistant started up the chainsaw.
Murphy looked at him with surprise and said “Bejezus, what’s that noise?”
Image used under a Collective Commons License from https://pixabay.com/photos/chainsaw-saw-tool-power-cutting-3523794/