Game Ideas are subjects that require patience to retrieve, trying to get others to give you ideas can often leave you with ideas that you may not be interested in making. Say for example most people give you the idea of making a shooter game, but you aren’t interested in them, if you ever feel like working on it, you’ll be demotivated by the time you start.
Game Ideas don’t have to matter whether they have been made or not, there are many games that take up the same genre, but usually they have a difference in content. Again with the shooter example, most shooters on Roblox are unique and feel like their own thing with the only similarity being the genre. Bad Business and Phantom Forces are both shooters, but the way they execute the genre are completely different, making them difficult to compare.
If you’re really certain you want to create something original, look through the Games page and see what has been made already and make something that hasn’t been made and see how well it goes. And example would be Puzzle games, you almost never see those on Roblox, with a few exceptions.
But generally the method you should use for Game Ideas are ideas that you yourself have thought of and are certain that that idea is what you want to make. Creating games on Roblox should be something that the developers made because they genuinely wanted to make, regardless of how profitable it’ll be or if it made already
A final note to mention is that once you think of game ideas, check if those ideas will actually get people to play them for any reason (it sounds fun or it’s unique, anything). Ideas that are overused to points where it can be annoying to see another one of them pop up will make users not play your game, leaving you with only a small handful that actually will play it, such as Simulators to name an example
If you have a problem sticking to an idea, then I think it’s best you create small games at first to get a feel for game development and then after you made a few small projects, you can make a bigger project if you feel ready
TL;DR: Make games that you want to make, that aren’t overused, have a unique aspect in them because ideas you generally want to make will motivate you to continue. If the size of a project is causing you to stop developing it, start by making small projects and then make big projects after a while
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