I wouldn't consider myself an elite trophy hunting expert or anything, I have killed one good buck and I know several people that have killed huge bucks. I think it is pretty clear that you have to have a combination of factors to harvest big bucks consistently. Obviously money will get you almost anything you want when it comes to deer or elk (Denny Austad comes to mind). Luck can also strike anyone at random. I saw a monster buck last year taken by a bumbling road hunter that had never killed more than a forkie and this brute buck was just in the wrong place at the wrong time (or right place at the right time) and of course I know several ranchers that have monster bucks hanging in the rafters of their barns off of their land.
I think though for the average Joe that doesn't have unlimited money and isn't going hang his hope on luck, and doesn't have connections to landowners, that hard work and time are essential and probably the only means of really getting a big buck. You have to be willing to go places people are not willing to go, take more time than most people would spend and you have to have the patience to stick it out and be willing to eat tag soup regularly.
For my buck, I had nailed the area as an area with some fantastic bucks because I had found some very good sheds in there year after year. I don't remember who has this signature but it's something like "you can't kill a big buck unless there is a big buck where you are hunting" You have to know the areas that big bucks like and be willing to go there. They are usually areas that are remote, rugged, isolated, roadless or a combination of all of these.
I think too that you have to see it as a long term commitment, not just 2 days of scouting before the hunt but alot of hours all year long getting to really know the land and the animals (where do they go when it's hot or dry, where do they go when it's stormy, where do they go when they are under heavy pressure, which springs and water holes are reliable in droughts etc, etc)
AND, you have to be able to keep quiet. You only have to tell one person something general like "I saw a huge buck on Fill-In-The-Blank Creek during elk season" and by the next year you could have 30 people hunting in there. And this can be the hardest part, you have to be willing to look like a poor sap who hasn't seen a big buck in 20 years in order to keep your quality areas, quality areas.
Again, I'm not expert, just some thoughts from a poor sap who hasn't seen a big buck in 20 years