There was so much I didn't know (there still is - in fact, the more you work at it, the more you realise you have to work out), but one thing that I did know was how I wanted my world and my characters to be. I had grown up loving fantasy, losing myself in the books of Tolkien, Eddings, Feist, et al, but I had also spent those years reading thrillers, from Forsyth to Fleming to le Carré, plus any of great or lesser renown in either genre whose book took my fancy. The result was that, when I started making my own stories, they were a mixture: they were fantasy, but leading with realism (no magic, mythical races or fabled creatures) and driven by a theme of adventure.
But it is this aspect of "realism" that is the tricky bit. What exactly is real? For example, one reader criticised the attitudes of adults in one part of Hero Born, allowing untried youths to venture forth unaided into danger. They even compared my characters' attitudes, detrimentally of course, to the philosophies of Sun Tzu. But does that make my characters less real, or more? Do all military commanders make decisions or hold attitudes worthy of the great Chinese strategist? Would that reader have found it unrealistic for generals to send young men forth to die in their swathes due to outdated tactics being used against modern weapons, and then to repeat the mistake relentlessly; would they have been disbelieving that troops would be send in scarlet tunics to fight some of the best sharpshooters in the world, setting them up like targets at a funfair shooting gallery; would they have scoffed at the credibility of a society routinely producing the hardiest offspring by leaving new-born babies considered weak, small or in any way deformed exposed to the elements to die. And yet the First World War, the Boer War and the Spartan, Roman and Norse cultures (among others) have given us examples of these instances from our own history. Likewise, rites of passage - formal or ad hoc - vary enormously from one culture and one time and even one individual to another.
What I am trying to say is that, as readers or authors, we cannot decide what would be real or implausible in another culture in other times based on our own values and views. Nor can we expect every warrior chief, actual or fictional, to follow the principles of one of the most influential military thinkers of our own history. Nor, when we can look at any busy high street and see one parent on a pavement refusing to let go of their child's hand for a split-second and another letting their toddler trail unseen behind them, can we assume that everyone views parenthood the same way; we may disagree with what some fictional characters do, but we cannot say no one would do the same.
If this sounds like an author's get-out clause, then that's because it is, for it precludes us from criticism of what we have our characters do and say. But it is a get-out clause based on the simple inescapable fact that we are all, as individuals, groups or entire societies, capable of more differences in opinion, outlook and approach than we can even imagine. A get-out clause can be a genuine reason for addressing an opposing view.
And as far as authors go, especially fantasy authors, it is most definitely a case of "My world, my rules, my reality". The trick as an author, however, is to make that reality believable within the confines of their book, and in my view that is all about making the views of a character consistent with him or herself and with the environment within which they are trying to survive.
Whether you achieve that can only really be discovered when your work is exposed to the opinions of the world of readers and, when that happens, it is also helpful to remember that, when one of them has a different view from you on whether or not it is believable, then that difference of opinion is just an example of reality.
Stay real, folks! Stay different!