When you look at the numbers (I presume you mean the number of CPUs, their frequency, the amount of RAM, etc), on the paper they all have something similar. How do you know if one has higher-quality RAM than the other?
There are lines of products (like macbooks or thinkpads) where you can check the quality of earlier models, but macbooks and thinkpads are on the higher end. My friends who want Windows don't go for thinkpads...
But that's not really the thing with the laptop recommendation question. It then comes down to how good of a hinge on the screen. How much flex does the body have when you actually hold it and use it. How janky are the ports. Does the trackpad and keyboard feel terrible to use? Do you feel like you risk cracking it in half tossing it in a backpack and carrying it across town? These are things where there aren't necessarily hard benchmarks and can be difficult to ascertain by just looking at listing photos.
Outside of some things like Thinkpads and Macbooks I often have a difficult time making real laptop recommendations without actually going to the store and holding the machine or hearing a trusted(ish) reviewer comment on the relative build qualities. It can be pretty easy to tell case rigidity when its in your hands. You can tell if a hinge feels like crap or not moving the screen a few times.
But I was talking about quality: how does one compare two laptops costing respectively 400$ and 800$? It regularly happens to me that friends ask help choosing a laptop. Sometimes they blindly trust me when I say "in your situation, I would buy that". Often though, they're more like "okay but you like computers so of course you would want a 'rolls-royce', but for me I think the cheaper one will be enough". Where actually my opinion was that both are not good enough for me, but the cheaper one is a piece of crap for everybody and the less cheap one is good enough for this particular friend.
The thing is, I can't blame them for not knowing how to compare two laptops. And the one thing they understand is price: they see two laptops that look similar, and one of them is half the price. The assume similar quality and therefore go for the cheaper.
Again, it's not that they don't care about quality, it's that they fail to estimate it.