My vote is my voice. If an incumbent doesn't deserve it and the opposition isn't worthy, my lack of a vote in that race should show the loss of support. The ballot count should tell a story, and that story shouldn't default to a lazily misplaced vote.
@MostlyPeaceful You assume he'll vote to represent the people in his district if he stays. He obviously doesn't do that enough or he wouldn't be getting primaried