[annapurna]

To separate things a bit: recovery from the surgery will, of course, be easier the more fit and healthy you are. As your pain increases, your overall health will suffer and you will see the effect in recovery time.

As your disk height decreases, your likelihood and severity of distraction pain will increase.

Your likelihood of a good outcome is affected the longer you go as your body starts changing other structures to account for the damaged disks. Facets, for instance, do suffer the longer you hold out with damaged disks.

The converse, though, isn't always true. Treating early doesn't guarantee a good outcome or fast recovery. I'll admit that I don't remember hearing of a person who had a good and quick recovery who was on death's door prior to surgery but that's strictly opinion based on limited anecdotal information.