I find judging to be rather formulaic. I write down what skills a girl does and the deductions and at the end I add up difficulty, event requirements, etc. Deductions and composition is very subjective, but routines go quickly and I don't have enough time to be thinking "oh, this is the first girl up, I should deduct more for that bent leg."
There was one meet that I watched (I wasn't judging this one) where a girl had a perfect bar routine. It was close to the end of the meet, and I would have given it a 10 because there were no deductions and I knew it was the best routine of the day. Had she been in the first rotation, I maybe would have given a 9.9 just because I didn't know if there would be a better routine. But a 9.9 would then have been the highest score of the day. The 0.1 deduction would have come from the composition category, and I would have had to stick with that high standard for the rest of the meet.