If you've ever tried talking with someone who doesn't seem to listen to you, you know how annoying it can be. You try to make a point, but they just run over it like a steamroller and talk about something that interests them.
Why is this so frustrating? Because, even if they don't mean to, these people send the message, "I only care about me. I don't care about you. You don't matter."
No one likes hearing this. Especially not potential clients--after all, why give money to someone who doesn't respect you? That's why it's so important to understand buyer personas and the buyer's journey--it helps you create content that tells customers, "We understand you, we value you and we have what you need."