I think from my experience with a bunch of different guitars over the years it boils down to:
Quality materials for the neck and body
Good string action that can be adjusted up and down
An intonatable bridge located in the correct spot
Level frets in the correct spot and of a reasonable height, scratch free, and ends that are not sharp
A smooth fretboard
A truss rod that works
Quality electronic components that are durable
Comfortable ergonomics for the body and neck at a reasonable weight
Pickups that work well and are adjustable.
Quality tuning machines
Correct gauge strings sitting in a quality nut
A durable finish material
Proper and accurate assembly of all components
What's missing if anything?
Quality materials for the neck and body
Good string action that can be adjusted up and down
An intonatable bridge located in the correct spot
Level frets in the correct spot and of a reasonable height, scratch free, and ends that are not sharp
A smooth fretboard
A truss rod that works
Quality electronic components that are durable
Comfortable ergonomics for the body and neck at a reasonable weight
Pickups that work well and are adjustable.
Quality tuning machines
Correct gauge strings sitting in a quality nut
A durable finish material
Proper and accurate assembly of all components
What's missing if anything?