Let's start off by discussing the absolute lack of CHOICE in dialogue options. Actually, we can't even discuss the "lack" of choice, because that insinuates there are at least a few. But the fact is, there are none. This game would be better described as an interactive movie that you actually don't interact with, just move the main character around in.
Every single quest, with the exception of a few SCRIPTED quest, has the same result for *every* dialogue choice selected. Get angry? Same result. Get snobby? Same result. Just say "ok."? Same result. It all leads to the same result, making multiple playthroughs impossible for immersions sake. There's no difference at all.
Don't want to do a quest? Nah, can't deny it. Just let it sit in your log. Want to do a quest in a way that's out of the box? Nah, can't do that, everything is hard scripted to the point of zero options at all.
Bottom line: Doing quest in Skyrim is like watching a movie. You can say certain things, but all choices lead to the exact same option, there is no branching, no choice. I would call Skyrim questing more along the lines of World of Warcraft (yes, I said it) than an actual RPG.
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The second thing that makes Skyrim dialogue so absurdly shallow is the fact that there is *no* descriptive text or voice acting whatsoever.
Quest giver: "Go here, get this." That's literally what is said. Oh, and then your map is updated and a huge arrow over your head is placed on an imaginary compass on your forehead. Oh, thanks. Cool. That's descriptive!
Morrowind quest dialogue: "In order to obtain this mystical sword, you must first take the Silt Strider to Seyda Neen. After arriving, you must walk through the marshes, passing the Delano Ancestral Tomb, and crossing the fjord. After that, look east, and pass between the two mountains that look like the humps of a Guar. Once there, enter the ruin. Be wary, traveler, as many vile things inhabit that ruin."
See how much more fun that is? See how much more descriptive that is? The REALISM? The DIRECTION? The actual use of landscape in the game world to give you an idea of where to go? That's AMAZING. Yet, in my over 300 hours of Skyrim, I have seen absolutely nothing but "Hey, go here. Get this. Ty."

Bottom Line: Skyrim's dialogue and quest giving is the most shallow i have seen in any game I have ever played, and I enjoy the quest text from an MMO more. It's sad, and shame on you Bethesda for treating your fans like 4 year olds. Maybe next time, you'll make an actual RPG instead of a hiking simulator.
