Writing isn't a net to scoop up every audience member and drag them along, rather each individual reader is their own net. And what they take away is what they take away. I did my best to get good grades in university and I did my best to retain as much as I could, but what was kept and what was lost is what it is. Writers can't impact each individual reader in equally. But if writers try, they can impact each reader in a unique way--and that is a home run.