Office chairs I'm very picky about. 1. The angle of the back has to be just slightly reclined back so my spine is straight but relaxed. 2. I love mesh material to ventilate so I don't get all sweaty. 3. Seat needs to be cushy otherwise my rear starts falling asleep. 4. No arm rests!!!! those things drive me nuts, take them off, take them away, ugh, be gone foul things. 5. Rolls easily 6. Adjustable height
Other chairs foot rest must recline Does not rock, seriously. low to the floor pillowy or streamlined designed upholstery,suede no leather. folds out to bed or long enough to stretch out on.
I get most of my comfort when I am able to sit the chair on my head, balancing it on one of the legs, of course.
But really, the majority of well made and albeit more expensive computer chairs tend to be adequately comfy. Hard chairs are a plain annoyance for me, for obvious reasons. I get more comfort from a well made couch rather than a chair though, you can't take on as many positions in a chair as a nice couch.
But some factors I believe to influence the comfort of any furniture you sit on are: Height; both how far the seating part is from the ground and also how high up it is against your back (above the shoulders is ideal I think without the need to slouch for it to be that way), cushioning, effective support of the back and neck and a relatively straight back to it, mostly because it's healthier for your posture otherwise you risk future persistent back and neck pains.
Back support is the main component! I'm fairly tall, and most chairs are made for much shorter people. They often press against the base of my shoulder blades, or right around there. I have to slouch to avoid the intense pain, and that doesn't work in the long run. As for my butt, it votes for firm, smooth support. If I might be there for a while, I don't want irregularities in the surface to cause sores or irritation...
A perfect chair for me would have to be one that not only rolled, had height adjust ability, Strong back support, but still cushioned, a comfortable seat, of course. None of that fake leather, or even real leather seats, I'll stick to my good ol' cloth cushions. And a cup holder. So you don't have to worry about knocking over a drink on your desk, it sits firmly in place in your chair.
My favourite chair is pretty firm and bulky, but with a belly juuuuussstt soft enough to use as a pillow. It's got strong arms and a gentle touch, and a persistently warm temperature, and usually wears extremely soft sweaters and it smells very nice, and if I fall asleep on it it will carry me to bed.
It kind of depends on what I'm using the chair FOR. I love my office chair that I use to work on the computer, but I wouldn't want to kick back in it and watch a movie. Although, in that instance, I'm more of a couch person.
Anyway, an office chair needs to be height-adjustible and have proper back support. A relaxing type chair needs to recline and have a footrest, and be large enough for a blanket and a friend (dog, cat, person, etc.). And er, somehow not be a couch.