Ok, I'll give you an example. At one point characters climb into a large faux rock in an environment that is described as containing many similar rocks. They transit a large distance by making this rock mobile, according to the narrative, hiding from satellites, etc.
The problem: technology we've had for many decades would catch them the first day out. Simple image subtraction. Imagine an image of a scene of any particular complexity represented as a series of numbers (pixel values.) Move something in the scene overnight. A day later, take a new image. In the context of the whole scene, you, with your human eyes faced with significant complexity (many rocks in this case) might not be able to pick out the movement.
Now subtract each pixel from image one from the pixel in the same location in image two and take the absolute value of the result. In all places where image 1 is the same as image 2, the values are the same, so the result is zero (which generally we treat as black.) But in the location where the object moved, the pixel values are not the same, so the image resulting from all these subtractions shows a spot of brightness (values above zero) in two locations: One, where the object was, and two, where it is now. From the perspective of the Red Mars storyline: address both spots, characters trivially eliminated or captured, storyline demolished.
This is one of the most basic (and effective) types of satellite detection of movement and change, and believe me, it's no secret.
The consequence: No such travel would hide them; the storyline is therefore borked.
From my POV, while these kinds of flaws will get past a certain percentage of the audience, they're not forgivable WRT the author (or the agent, or an editor familiar with the genre); if you're going to write SF, particularly SF that uses technology to actually inform the storyline, you had better make sure that at *least* your postulated idea hasn't been obsolete for a quarter of a century. It takes research. You can't just sit down and write about this stuff, you should know it first, or if you don't, you need to fix that. Or your support team needs to catch it -- and that's still your responsibility. In this case, the premise was hiding from satellite surveillance; even a cursory check of the public subject matter would have found that the method described would not work.
Not to just beat up on KSR; Sometimes it's simple anachronism; for instance, in a future written about by Anne McCaffrey where we've been in space for a while, and the characters are at a new planet discovering dragons, mentioning the "floppy drives" in the spaceship simply shows a failure of the ability to think ahead -- it's just not reasonable. James Blish, in Welcome to Mars, had his character use a "power tube" to build a technical transport widget critical to the storyline; in a future far removed from vacuum tube technology. Said tube breaks on landing, and so the characters are stranded, and on this premise the majority of the adventure is based. This is slightly more forgivable, given that at the time, tubes actually were the tech at hand, but I still rather think it was some weak writing from an otherwise capable author. I had the chance to call him on it, and was rewarded with kind of a hangdog look and a nod.
SF authors -- if they're serious -- need to find people who can do this kind of checking. It's important, particularly if you're going to be (or hope to be) hanging with the big dogs. Because eventually, someone will call you on your errors, and on such things reputations and careers can rise and fall. It's just that simple.
I recently had the distinct pleasure of working with an author, a new one, who not only did a good job out of the gate, but was amenable to having flaws such as the above pointed out, corrections made, references provided and checked, etc. I think the work is top notch; we're doing all we can to get it published, but alas, right now the term "new author" is another way to say "not getting published" by any of the major houses. They all seem to be running off backlists and the lack of foresight of many agents to reserve electronic rights, allowing them to produce e-book titles at little cost. I think we'll get him published one day, simply because the work is truly excellent and because I (fervently) hope that these conditions will not persist forever. As long as his patience holds out, anyway. He could at any time throw up his hands and go straight to e-book, which might indeed get him launched, but carries many downsides that would be particularly galling to see afflict a work like this. It's a frustrating time to be in the business, I assure you of that.