Some writers can be douchebags. I am one of them. Some writers are civil - nary a unkind word passes their lips. I am one of them.
I'm basically however you treat me, however you regard me, however you respect me. And I don't mean solely in direct communication - this is in anything you do. If you treat me like a king, but shit on your friends, you will earn my ire. If you slack off in your work, or behave like a Nazi, then I will treat you like the lazy-ass or holier-than-thou moron you are.
And if you write terrible prose, and act like you're the shit, I will treat you as such. I have no tolerance for bullshit.
Come on, jerk-off. What do you think's in it for me? To take the time to read this, give you advice and feedback, and then you just ignore me? Do you think you're impressing anyone by calling your drafts "Test Type" and "Prototype"? Do you think anyone's going to read a rehash of the canon material, long paragraphs, and little dialogue? You're failing, and you don't even know it. I am the football coach grabbing the nine-year-old who's not listening by his helmet and shouting "I am trying to help you!"
Arrogant? No, just realistic. You're the arrogant one, because you think you're above simple instructions. Those weren't even my words. They were Orson Scott Card's! You know, "Ender's Game"? Multiple Hugo and Nebula winner? Better writer than you'll ever be? (or me, to be fair).
I told you exactly the type of beta reader was. I told you I showed no mercy. I told you I had no time for etiquette or fancy wording. I told you I pull no punches. I told you I don't get paid for this, I owe you nothing. But at the heart of it all, I'm still following a good reason - I'm trying to help you become a better writer.
But if you want to ignore me. Fine. Saves me time. I can't wait for your reviews to pour in.