Some things I can write-up on an inspection before I even get to the property. Among those items is the electrical wire for the water heaters. It is seldom installed in a conduit for protection. Many of these heater locations are in the garage and laundry rooms where all kinds of clothing, tools and miscellaneous items are hanging off from this exposed wire.
This picture is one from today on a brand new home.
So, if your wire at the water heater or elsewhere is exposed to human peril, please put it into a conduit for your protection.