All I know is, most of today's laptops fail really quickly (in like couple of years). Mostly due to cracked solder balls on GPU.
No longer a problem afaik, the bad solder was due to bad lead-free solder used for attaching the BGA when they first switched to lead free solder. This is why many say you can fix laptops from that generation by sticking the motherboard in the oven. I believe nvidia was sued over this; but don't think this is a issue anymore.
All expensive ones. Latitude or Studio can not compete XPS, AW or Precision, which is obvious.
For the same reason, for Lenovo, Think X/W/T and Yoga/Think Yoga are always better than Think E or ideaPad.
Studio is XPS: "XPS Studio", but I don't think they use that brand anymore.
Latitude is their business line, XPS is high end Consumer, no idea what AW is (did you mean ATG?), Precision is workstation. Lower end consumer line is Inspiron.
Perhaps you mean Inspiron cannot compete with XPS, Latitude or Precision?
Yoga is IdeaPad; "Ideapad Yoga". Also the ThinkPad Yoga 14 is pretty bad, probably ThinkPad E tier (I mean, they sell them in Best Buy). The Yoga 12 is much better, as it's technically under the X series I think.
I would imagine the new X1 Yoga is better.