The primary purpose of an electrical service drip loop is to prevent water from

The primary purpose of any drip loop is to prevent water from getting into the house.

If you run a wire down the wall and into the house, water will follow the line created by the wire.

However, if you make a small loop of wire under the entry hole and then run the wire up and into the entry hole the water will drip off the loop and not enter the house.

Sounds like another homework question to me!

The primary purpose of any drip loop is to prevent water from getting into the house.

If you run a wire down the wall and into the house, water will follow the line created by the wire.

However, if you make a small loop of wire under the entry hole and then run the wire up and into the entry hole the water will drip off of the loop and not enter the house.

To add, it's to prevent the water from getting into the electrical equipment. ;)