Not to be too anthropomorphic but I liken mature bucks to old men. They're tired, arthritic, in constant pain, stiff, have lost much hearing and sight, and generally have incredibly low tolerance for extended social pressure. So they hole up alone where they're not likely to be bothered or forced to move, and they only get up when they need to eat then right back to the recliner they go.
During rut, if they rut, they have a gigantic loop mapped out out where they already know from experience there are going to be hot does at specific times. He slowly but surely covers that loop, not chasing young does but rather breeding their mother's and grandmothers that are expecting him.
I could be entirely wrong about that but it's the only way I've been able to make sense of old buck behavior. Most of the biggest oldest bucks I've killed were expected because they had been through before around the same time. Not not before and not after, but inside a very tight window of days. The first buck i killed this season was a perfect example. Years of pics during early November only. He came out tending an old doe and was stiff legged and slow. He could barely run. When butchering I found his right front ACL was gone and knee was calcified. He came out around other deer only to breed. Otherwise he stayed laid up alone somewhere.
