Most memoirs fail because of voice. It’s not distinct enough to sound alive and compelling. Or there are staunch limits to emotional tone, so it emits a single register. Being too cool or too shrill can ruin the read. The sentences are boring and predictable, or it’s so inconsistent you don’t know who’s speaking or what place they come from. You don’t believe or trust the voice. You’re not curious about the inner or outer lives of the writer. The author’s dead in the water.
– from “The Art of Memoir” by Mary Karr