Creating a game, is literally the most complex thing in existence, as you're literally creating your own entire world/universe!
Demands of Game Making:
1. Authorship: writing ability: story, plot, dialogue, setting/mood, literary themes, history, emotional immersion, intimacy with characters (love them, hate them, laughing yourself to death to them, struggling with them, etc etc etc), etc
2. Programming: coding ability to actually do/create everything that you want in your game and for your game to be able to do
3. Designing: able to design an entire game, what is your game, what are the features of your game, etc etc etc, and a really good, fun, smooth (such as game controls and/or movement for examples), etc game at that
4. Media: music, sound, voice/speaking, art/graphics, animation of art/graphics (Programming+Media), etc etc etc
5. Math: game mechanics, game balance (this also falls under Designing too), 3D world movement and etc physics involved, etc etc etc
6+7. Business+Law: the profit+legal side/part of game making: advertising, marketing, game making, legality, copyrights, etc etc etc
8. etc etc etc stuff I can't think of...
---------------------
everyone has different tastes, so it's a matter of how good/well you do what you do. Mozart created great music, Picaso created great art, Bill Gates created a great product, etc etc etc. Whatever type of game you create, it must be a great game of that type of game.
a game must INTEREST the person for them to try playing your game and for them to enjoy playing the game; your game must be "sexy" - it has to catch their eye/mind-brain and keep their eye/mind-brain.
AND, it depends how much work you want to put into it... compared to how much work you're actually able to (end up in) put(ting) into it... be REALISTIC about your ability, time, and duration of motivation/interest !!!
However, in terms of what people are interested in, there are some universal tastes (as we're all human organisms), some of which I discuss are here (all are aspects of RPGs):
(the ultimate two main interests of people playing a game: CUSTOMIZATION AND CONTROL)
viewtopic.php?f=20&t=3877#p25944 (see my post in the link)
also, if you don't already know, read emily short's articles on game making/design:
https://emshort.wordpress.com/ (main page of her site)
her articles:
https://emshort.wordpress.com/how-to-play/reading-if/https://emshort.wordpress.com/how-to-play/writing-if/https://emshort.wordpress.com/how-to-play/teaching-if/--------------------------
and if you're into art/graphic design:
http://tutsplus.com/authors/joumana-medlej (there's 4 pages to look through, especially look at pages 2-4, which has all the stuff on drawing, and even the science of, human anatomy and their behaviorisms/body languages-expressions, WOW!)