Cheap systems = cheap cases and a lot less sturdiness and bracing of the case and keyboard. People treat laptops like they are rocks, they grab them when they are running and run across a school campus with them, toss them on the bed, lift them by the lid when opened, etc...
Plus they are just slow and many people think just because it's a computer it will do anything that any other computer will do and just be cheaper. If this laptop is $300 and the other is $1,000 I'll just buy the 300 and save 700. Oh, hm.. why won't this open 10 things at once and play my games??? I need to buy a faster CPU and video card to make it faster. Oh, what, I can't? Next step is selling the thing for 1/2 of what you bought it for a month ago and looking for a faster one anyway.
What I tell people to do is buy a used $1,000 laptop that's 2-3-4 years old for the same price as a new one. Lenovo ThinkPads are my go to systems. You can find a used T410, T400, T420 for the price or a new low end system and will have 3 times the laptop quality and speed or the same price. And with how solid they are built, no-one will miss on not having a one year warranty on a new laptop.
I've sold probably a dozen T410 and T420 systems past year and everyone that got one has been thanking me for steering them to those. One of them actually ended up in the hands of a city mayor through someone else that bought one from me and I was told he loves the thing.