safety rule

Hi all,

This list must have hundreds of 1000's hours with automated (CNC)
machines so would be a good place to ask this question (poll).

One of the safety rule says that one should never leave an automated
machine running unattended. But this would negate one of the greatest
advantage of automated machines, and I am sure that (unattended) is
often done.

Just like to find out how list members had fare when they did (leave
cnc machine running unattended).

a. done that numerous times, everything fine
b. done that, and had a very bad experience. The .........
c. Heard that this happened to someone when he/she (any she on this
list?) left the _____ machine running unattended. The .......
d. rules are made to be adhered to strictly
e. rules are made to be broken
etc. etc.

Andrew