Practice, Patients, and Persistence.
There are many times it comes down to being at the right place and the right time.
As a hunter, you need to be patient, and persistent.
There are a lot of factors when hunting that you simply cannot control. Weather, hunting pressure etc.
You also need to know the area you are hunting. You mention using calls and multiple scents. I shy away from this. Calls especially since where I hunt the buck to doe ratio is more like 1:10. Why would bucks be fighting over 1 doe when there are 9 others waiting close by.
If you are doing all the right things, ie: getting to your stand quiet, taking into account the wind, masking your scent, things will fall into place. It is not easy, but you must be patient and persistent.
Sometimes you need some luck. I would not say skill so much as experience. I am ten times a better hunter than when I started. You learn how the deer react, what you can and can't do, how to be quiet, shots to take and not to take.