It really really really really gets my goat when I have to not only sift through a superfluous amount of confirmations, but to have them all defaulted to "No" or "Cancel". (Not every time, which can be just as annoying due to the lack of consistency)
Confirmations are fine, but confirm the decision, not challenge it...
If you are really taking the UI experience seriously, please take note that there's an unbelievable amount of redundancy in the game, and that defaulting to 'Cancel' when you have an actual 'cancellation' or 'escape' button is annoying and just impractical.
Please assume that the majority of the user base knows what they're doing, and that they are in fact interested in talking to the NPCs they're talking to. Please also assume that if they were to accidentally talk to an undesired NPC that they possess the ability to hit the Cancel button, and don't typically wait to the end of sometimes lengthy dialogue boxes to cancel.
For example:
The process of selling an item on the auction house:
[Highlighted in blue and red to symbolize reasonable and unreasonable actions during the process.]
1) Talk to the Auction House window or NPC.
-- Drop down appears, Buy/Sell/Sales Staus.
2) Select 'Sell'
3) Select item from your inventory.
4) Set Price.
5) Arbitrary Menu "Sell | Cancel" defaulting to 'Cancel'.
6) Select 'Sell'.
7) Arbitrary Menu "Transaction Fee" defaulting to 'Cancel'.
8) Select 'Ok'.
9) Confirm Price. Defaulted to 'Cancel'.
10) Select 'Ok'.
How these transactions should be streamlined for the users:
1) Talk to the Auction House window or NPC.
-- Drop down appears, Buy/Sell/Sales Staus.
2) Select 'Sell'
3) Select item from your inventory.
4) Set Price.
5) Confirm Price, and Auction House fees, Defaulting to 'Yes'.
And finally: The "Have a nice day!" ending lines need to be passive, and not require action on the part of the user.
For example:
Teleports could be a three step process:
Talk to the NPC,
Select destination,
Confirm.
NOT the five step:
Talk to the NPC,
Select destination,
Confirm, defaulted to 'Cancel',
Select 'Okay',
Confirm "Have a nice day!" (That ironically you can't cancel out of).
You don't go to a restaurant and order food like this:
Waiter: Welcome to Chez Square! My name is Mondo-Gordo, what could I get for you this evening?
You: I'll have the Rib-eye with the seasonal greens and roasted baby potatoes.
Waiter: So you don't want the Rib-eye with seasonal the greens roasted baby potatoes?
You: No, I do.
Waiter: Excellent, the price is $25.00 for the meal. I assume you wouldn't like to pay that, would you like me to cancel your order now?
You: No that price is fine.
Waiter: Alrighty, your order has been placed.
You: Thank you.
Waiter: Have a nice evening!
<Waiter stands there in an uncomfortable silence...>
~Please.