I watched some of Cliff’s videos. In one of them, he talks about food being either one of the central problems guys run into, possibly (can’t remember for sure) of the main reasons people quit early. Following some hunting FB groups, the complaints, excuses and seeming lack of preparation support this.
Seems to be the case that a lot of newbies don’t put much thought into food and, even then, many who do put some thought into it do not seem to test and experiment. A lot of guys claim that food isn’t important to them and that they take the “if it makes a turd” approach, but few actually fall into that category. Food is highly personal and also very psychological. You need to figure your food out or you are going to break down.
Next up, I think a very general lack of backpacking/camping experience is a very overlooked factor. You need to know how to camp (wherever style camping you will be doing): you need to be efficient at it, you need to be comfortable and you need to be able to sleep well. This is literally the easiest aspect of hunting to prep for. Regardless of where you live, go camping. A lot. Get good at it, dial your sleep setup in, test your equipment, set it up and break it down often. You need to be a good camper if you are going to camp and merely camping while you are on a hunting trip is going to create more problems than it is going to solve.