It seems that, when entering a batch of Sales (maybe purchase too, I don't know) quick entry transactions, the system will allow you to just press <Cancel> instead of <Save> and bin the whole thing with no second thought. This is very odd behaviour, considering the two buttons are right next to one another.
Ideally, both buttons should have a confirmation dialogue before actioning, but especially <Cancel>.
I had a user lose a large batch and I had to then see what happened. I was amazed to see I could just bin an entire batch with no warning.