Ok, I understand what you're getting at now
The two main hormones our thyroids put out are T3 and T4. Therefore, when we become hypothyroid these levels drop in our bloodstream. So we order the free T3 and free T4 labs to see what our levels are and whether or not we need treatment. These labs have ranges and most of us find that we are hypo if we are in the lower two thirds of the range. So if my labs look like this (which they did, not so long ago):
FT4 -- .86 (.61-1.76) 22%
FT3 -- 2.7 (2.3-4.2) 21%
My free T4 is only 22% of range and I need to try to get it up above at least 50-75% to feel better. My free T3 is only at 21% and it, too needs to be much higher. Just exactly how high in range you need to get is an individual thing and therefore we go by symptom relief as our main guage of wellness.
The TSH is not something that we hypos pay as much attention to. It's often used to mis-diagnose and mis-treat us and mine was never out of range even when I was raging hypo. The clinical guidelines most mainstream docs follow tell them to watch TSH levels and keep them within range at all costs, mostly to the detriment of a patient's well being.
Hope this helps!