Live is definitely my yardstick. Making recordings and playing live can be two different art forms.
I've made some people sound good in the studio who absolutely suck live.
But on the other hand, I've recorded some guitarists who can nail complex harmonized leads in one take per harmony, definitely something impossible to do strictly live.
The first time I recorded in a studio I didn't haul in my effects rack. It was just supposed to be a demo tape we were doing to mail out to prospective clients. The recording engineer and studio owner was Paul Hornsby of Capricorn Records fame. He had a wall full of gold records from those days as chief recording engineer with Phil Walden. He was chief engineer on Marshall Tucker, Charlie Daniels, Wet Willie, Allman Brothers, and pretty much the whole list of Walden's southern rock artist portfolio from that era.
When Phil moved the studio to Nashville, Paul decided to stay in Macon, Phil gave him the console and the complete set of tape drives and other peripheral equipment as a retirement present. Paul got pretty much the entire recording setup that he used during the 70s. Phil was building a state of the art digital studio in his new location. That was in the early 80s and Paul still runs the same small studio, doing demos and CDs for local talent and some that tour the nation.
We all plugged into his little tube amps that were set facing padded walls and corners and tuned up. My Strat sounded pretty thin, so he proceeded to fatten it up. Woah! In about 60 seconds I sounded like a million dollars.
A good engineer can make the difference, that's for sure.