Still, sometimes the temptation to use authorial intervention to solve an intractable or just difficult problem is too much. I notice it frequently in works of fantasy, where it almost seems to be a staple of the genre - prophetic visions or clairvoyant revelations that give the characters insight into the future, and also serve as easily-installed motives. Say that you've got this sorcerer in a far-off land who you plan to be the Big Bad of the series, but your characters have no reason to even be aware of him, let alone willing to challenge him. Sure, you could weave a complex plot together where the protagonist and the antagonist gradually come into each other's lives through ordinary circumstances and invent their own reasons to stand in opposition - or, you could just have some convenient soothsayer grant a character a vision of what this sorcerer will do when he achieves the power he seeks, and motivate the protagonist to prevent that vision from ever coming to pass.
Personally, I feel that pulling that particular trick out of the writer's toolbox cheapens the work. I believe that a protagonist should travel through the narrative and emerge victorious on their own merits, rather than because of some ineffable gift of second sight.
It's when this same line of thinking shows up in science fiction and other, more reality-rooted genres that I really start to get irritated. Fantasy gets a pass for a lot of things specifically because it is fantasy; the whole genre is practically a paean of longing for things we can't have because the universe is a meanie. To be perfectly blunt, I expect better from things that claim to be science fiction. I speak, specifically, of the Enhance Button.
Zoom in on A4 and rotate the bitmap around the Z axis all you want - the only thing that matters is that pixels gotta come from somewhere.
It's a staple both in modern science fiction and police procedural/mystery shows for the magical computer to take a small, grainy, poorly-resolved image and transform it into something of perfect sharpness - generally it's a key clue or deciding piece of evidence for the main characters, and without it they would be flailing about like a fish on the dock.
This is nothing more than an expression of the same motives that lie behind fantasy's prophetic visions - and, hell, science fiction frequently incorporates prophecy like it's no big thing. Look at Minority Report - without precognition, the story would fall completely apart. More recently, you can find it in StarCraft II's reeling, staggering narrative with the Ihan crystal missions.
What crystallized this for me was a two-part episode of the mystery series Castle, which I can watch thanks to CTV streaming it on their website. In the second-season episode "Boom!," the NYPD is on the trail of a crazy killer who has sent a video of himself with a captive to taunt them. Fortunately, the characters have a magical computer at their disposal. Not only are they able to zoom-enhance a light-drowned corner of a window into a recognizeable image of a New York City bridge, they're also able to completely strip out parts of the audio track with a few keystrokes, thereby isolating the sound of a passing elevated subway train. They then use the sound and the angle of the bridge view to establish precisely where the killer was holed up - and all this in barely more than sixty seconds.
What makes this even more hilarious is that, from the way the rest of the episode unfolds, the killer had expected the police to discover exactly this.
I know from experience that one of the hardest parts of writing is making a worthwhile villain, because they don't have the decency to make some elementary, stupid mistake that the protagonist sees through in an instant. But to create a villain that does cover his bases and have the protagonist make her way to him because of revelations from a magical computer or a prophetic vision doesn't do a work justice.