lol that's not the reason why QTE's are implemented in games.

The reason for QTE's is very simple. QTE's are in games because they give satisfaction to the player by successfully performing a very simple task.

I don't mind them as long as they don't break up the action too much, or punish you severely if you miss an input. The worst kind of QTE's are the ones that lead to your early demise (cheap death) if you happen to miss it.. or press something other than whats been stated . A number of games do that these days and its annoying as hell.

German TV show Game One summarized it quite well in one of their shows. I can't really put it all together but it was about QTEs that feel forced and out of place vs. QTEs that add something to the game that wouldn't be there without it or a lame cutscene.
They had an example of one QTE where you had to do it to cross a bridge (I think it was a tree crossing a gap or some plank or whatever) with one of two characters. When you finally managed to get across after multiple fails you'd meet the other character who used an elevator or something lol

I dont aprove of QTE's either. They make it difficult to enjoy the cinematic in front of you because you are more worried about quickly reaction to the button prompt.

I think QTE are ok as long as they are used correctly, for example in God of war where they are optional in most enemies and performing them yield different rewards like more life orbs or a special move that petrifies all enemies on range. QTE can be something good while they are optional and give something in return and are not as frequent. Then again if they removed them I wouldn't mind xD

This!  A thousand times this.

Mostly, I despise QTE's.  The only time I've come close to enjoying them was FF XIII-2, and even then I could've done without them.  The best thing about XIII-2 was that it let you know it was going to be a QTE before it occurred - "cinematic action" or something would pop up on the screen so you'd know what was coming.  None of this "it's a cutscene - NO WAIT LOL QTE" rubbish.

I understand the rationale of a QTE: a series of button presses which allows you to do "something awesome" in cutscene form. As long as that's what the developer is doing, that's OK. Just don't make the QTE too punishing on the player because that ruins immersion *(Ehem. Asura's Wrath).*

But a QTE to climb a rope is where I draw the line. That should be done just by pushing "up" on the analog stick.

The subjective quality of QTE's depends if or not the game is exclusively available on your console of choice

Paper Mario doesn't have QTEs.

They are enjoyable when:

1. They are in Asura's Wrath.