According to "stealth" errata in Essentials, XP are awarded for a skill challenge whether the characters succeed or fail.
But neither "succeed" nor "fail" includes "avoid", which I'll touch on below...
As I've often commentd, the function of XP in 4e is very different from in classical D&D. (I won't purport to understand the point of XP in 2nd ed AD&D and 3E.) In classic D&D, XP are a reward. Better players expect to earn more of them; weaker players earn fewer. Poor players might spend a whole evening making a hash of a dungeon raid, having few combat victories and collecting little treasure and hence getting little reward for their efforts.
Interesting take; as in everything before 4e I've always seen xp as a *character* reward, given via the player. This ties into my long-held view that a character is still part of the party even if the player is absent that session, and still earns xp etc. Further, characters only get xp for those things in which they actually participate - did you take part in killing those Orcs? Yes? Good, you'll get a share of the xp. Did you run and hide from the Orcs? Yes? Sorry, no xp for you.
This goes against what 3e suggests (everyone gets xp for everything, regardless) and what 4e seems to assume (the same thing).
In the same vein, some DMs give out character xp for things done by the player e.g. bringing snacks to the game or writing a detailed backstory. Bleah!
In 4e, XP are bascially a pacing device. Provided the players are actually engaging the game - resolving encounters (be they combat or non-combat) in a way that engages the agreed story focuses of play (ie earns quest awards), they earn XP. In DMG 2 this is even extended to the idea that non-encounter-focused but serious exploratory play earns XP. The basic rate is around one level-appropriate monsters worth per quarter-hour of play. Hence, provided that players sincerely play the game, their PCs will advance in level, thereby progressing through the stages of the game (heroic, paragon, epic and the endgame).
At a frightening pace, I might add. Level advance should be a side-effect of play, not the main focus of it.
Awarding XP for failing at a skill challenge is part of this. But if the players "avoid" a skill challenge in the sense of (say) teleport around it, and hence engage in 5 minutes of play rather than 1 hour of play, then on the 4e logic XP shouldn't be awarded. Obviously the players didn't want to play that part of the game, they wanted to do something else - so let's have them do that, and then award XP when that has been done.
If the teleport got them around a known* obstacle that would otherwise have required a skill challenge they should get the xp for it. (or, in my view, the xp should be divided between the character(s) who thought of the teleport idea and the character who cast it)
But let's take a more basic example. Let's say that written into a given adventure is this skill challenge: a cliff the party needs to climb in order to reach the adventure site at the top. They don't have flight or any other magical means of help. They can succeed, and climb up; or they can fail, and fall. Or they can avoid it completely by
finding another way around and coming at the adventure from another direction!
This is what should earn the same xp as beating the cliff.
* - bypassing something without ever knowing of its existence doesn't count.
This is also why 4e, more than any other edition, lends itself completely to "level when the story makes it appropriate" approach - and the DMG expressly canvasses that option (p 121), the first to do so as far as I'm aware.
This is a mechanic which for a bunch of reasons I don't like at all.
First, if levelling is by DM handwave either a) everyone levels at the same time whether they deserve to or not, or b) the DM will inevitably end up (rightly or wrongly) being accused of playing favourites.
It also goes against having a party with varying levels in it, which in a system that has permanent level loss along with occasional items that bestow levels is going to happen. And when it does, an across-the-board handwave system means the lower levels will never catch up to the higher. In a standard J-curve advancement system the lower levels will slowly catch up in number, if not in raw xp; as in a 4th-level chasing a 7th-level; by the time the 7th gets to 8th the 4th will probably be 7th.
And, it goes against characters being rewarded for what they actually do in the game. If character A is always sticking her nose in and taking risks in order to move things forward she should be better rewarded *by the game* than character B whose only concern is his own safety and who hides at the first sign of danger.
Lan-"when in doubt, charge"-efan