If you are in business, you are there to make money. If you do not make money, you cannot stay in business. You would think that people that go into business would get this, but one need only look at the pile of failures caused by denying this fact to see that it is not so obvious to many.
If you are in some form of entertainment, then your business revolves around knowing what your audience is and satisfying their demands as best you can. If you do not do this, then you will not make money because a competitor will do that better than you and your audience will leave you for them. As with the above statement of fact, this too is not as obvious to many as it seems. Far too many people in some form of entertainment think otherwise, and end up on the corpse pile accordingly.
If you seek to create tabletop RPGs in a commercial capacity, then you are in the business of doing so, and you need to know what your audience wants if you want to make money from selling them tabletop RPGs. The tabletop RPG business community has not been so competent, institutionally, for most of its existence. Stop doing that; you are direct contributing to your decline.
So, that said, it's time to take the last week or so of posts and make something useful out of them. Here we go.
Who is the audience for tabletop RPGs? By process of elimination, it's the gamers who want the full potential of the tabletop RPG medium. (If you want a full enumeration of this, come back tomorrow.) Gamers who only want a portion of it have their alternatives now, so stop chasing lovers that spurned you.
You need to know what your game offers so that you can tell them, in plain and simple language, what they can expect from playing your game. You must tell them what they are doing, and how they do it, without ever having them crack open a rulebook. In short, you telling them this is your marketing campaign.
Your ruleset must be as simple as Original or Basic D&D. This means that you must tell your audience that your game relies on the Game Master to issue rulings because your ruleset's mechanics are cover basic principles first, then only those specific subsets that every group must deal with. Everything else is left for the Game Master to specify when and how he desires. This means that you don't need to sell a setting, or that you need to have a hefty tome of uncoded videogame mechanics. (Note: This also means that your upper limit on mechanic design is "If this can be turned into a videogame, you've gone too far.")
Your business, therefore, is not in selling the rules. That's your loss-leader. Your business is in attracting a like-minded customer audience and facilitating their desire to play your game by helping them meet other players and play your game; if you're thinking "eHarmony for Tabletop RPG blended with LinkedIn and Tabletop Simulator", you're walking fire towards the target. That's why I disdain the talk about selling your game, because the game isn't your product; the money in tabletop RPGs is in facilitating connections between users.
More on that over the week.