Or production.
Good so far.
Should correctly be
Then you spoil it. The watt hour is a quantity of work, equal to 3600 joules.
Watts = work/time, hence watt/hour would be energy per time squared - joules per (second squared *3600). Not a lot of use for that.
Correct, quantity of work. Named after the 18th century English brewer who first measured the mechanical equivalent of heat. His brewery cellar was the ideal, probably the only, place at the time with a sufficiently uniform temperature over time to enable the experiment. His results were surprisingly accurate.