I was a complete nitwit when I was young. (Husband would say, no change there then!) I had some right disasters when doing my 'odd jobs':-

I once let the potato-peeling machine run on for too long, and the thing grated and grated until the spuds came out the size of peanuts.

I put far too much artificial cream liquid in the big whisker, and it beat the stuff into a massive foam that flowed over the entire kitchen and engulfed everyone up to their knees.

I collected up the false teeth for the geriatric patients and cleaned them all beautifully. But I didn't make a note of which were whose. So had to go round trying them all in different mouths. I bet several got someone else's teeth!

And selling children's vests etc in Edinburgh, I wasn't familiar with all the different Scottish banknotes, and happily gave change for £10 for every £5 I was handed. No wonder I had a lot of customers!