Who has thought about it? If you thought about it or are working on a project, then how might it compare to pre-made? If you have built it, well, how would you compare your finished product?
How much do you figure it would cost or what did it cost? Where might you buy the materials or where did you buy the materials?
Some of the pre-built computers, they cheap out on certain components, like the power supply, or the power supply is proprietary for the motherboard. They’ve gotten better recently, so there are times now where the same setup is either slightly cheaper or negligibly more expensive than doing it yourself.
Tbh it’s not really as big of a deal as people make it out to be. If you’re not that particular about what you want/need it isn’t a big deal. Especially if you’re not gaming it it, just grab anything that has decent enough reviews.
I built my own ANd I can do it again anytime I want and anywhere I rather build my own than have to buy a pre-built.
I repaired old desktops to laptops and whatnot It's fun but takes time, plus at least you are knowing what specs/hardware that you be getting and picking what you want.