Roblox vs Unity
To begin with, both Roblox and Unity game engines are accessible, fairly easy to learn, and have huge support communities attached to them. Let’s closely examine the points that stack in favor of either of the two-game creation platforms.
The Roblox game engine was designed for beginners. It is a lot easier to learn and digest compared to that of Unity. Both have their specific ways of doing things, but the basics like map making, importing third-party assets and resources, and the primary world and game-building mechanics are similar and standard as far as 3D game engines go. To put things simply, you have to program (or give sets of instructions) to the game engine, along with the environment, characters, and objects you built or imported, to have a self-contained executable game. With all the pieces in place, it will be up to your programmable game engine to execute.
Game Programming
This brings us to the next factor of the equation to consider: the programming language that the engine knows and understands. The thing about programming today is that things are done modularly, like a jigsaw puzzle you have to put together. For the sake of discussion, game programs were written in one swoop back in the dawning of game development (70s to early 80s). This meant that the entire code, game engine, assets, objects, sound, and the rest that comprised the total game were fitted into a long list of instructions, which could fill up rims upon rims of printer paper.
The modularity was expressed in terms of subroutines, and when written in Assembler or Machine Code instead of BASIC to speed things up, disconcerting confusion hit the roof. You guys are so lucky today that coding is done in a modular way. Now, all you have to do is decide which computer language would be more comfortable for you.
Roblox uses LUA, one of the easiest programming languages to learn. The language reminds me of LOGO (Turtle Graphics Programming), where instructions are given in their simplest, straightforward form. The disadvantage, however, with languages like these is their simplicity and their limitation in providing instructions on what and how to do things. Again, this is why the game programmers of old went for Machine or Assembler, as instructions could be executed in a far more detailed and flexible way.
With how the Roblox game platform and system were built, LUA would no doubt be an ideal programming language for young and adult game development beginners alike, as its ease of use and learnability will make it an excellent user-friendly environment for the Roblox crowd.
Unity is a game engine that hasn't been shy in going toe-to-toe with Unreal or ID's game engines. Unity (believe it or not) is quite powerful and fabulous (if not perfect) in making stand-alone indie or AAA games. It uses C# for programming, and going back to my historical analogy, it's like using Assembler as compared to BASIC. C# is much harder to learn but more accessible than the dreaded C++. C is a language used for speed execution because it is close to Assembler and, as such, nitty-gritty.
Therefore, its speed, flexibility, and detail in creating and executing instructions can make games that rival Unreal in many ways. It's also a lot simpler to learn than Unreal or even Source, for that matter. However, it is not suggested for game development beginners unless you've been into programming for some time (years) already. However, if you’re starting up and feel that you have to follow closely in the footsteps of your game designer ancestors, by all means, be my guest.
Quality and Limitations
Now that we've cleared the coding reasons let's take a quick look at the game and graphics quality. For this, the round will always go to Unity. In reality, however, some games don't have the looks or the smooth moves (so to speak) but have the addictive and immersive quality to reel in millions of gamers. So, it depends on the game maker and their smarts to get the game through. Note that any Roblox game will always be limited by its platform, as you can only do as far as the platform lets you. This is a clear disadvantage compared to having much more freedom if you make the game with Unity.
If you're starting up, however, file it as something to consider when you have the experience to show in making games. Just grit and bear for now that a Roblox game will always look like a blocky Roblox game, but in a gaming platform where the usual character looks like a refugee from Minecraft, there isn't much to complain about.
Support and Resources
The most important thing when tackling game development is the availability of support and game resources. In that, Roblox wins the round! Whether it would be tutorial videos on the Roblox site or YouTube, there are myriad tutorials in almost every aspect of Roblox. Whether creating characters, mapping, LUA programming, or the dozens of Roblox games to join, they have it just for you. What’s more, many Roblox members are willing to share the needed info and tips with you. Just ask around, and somebody is bound to answer.
Unity has likewise a considerable support base, though it's a bit more general on how to use and design games with the engine. Unlike Roblox, which is tied to a platform with over a million users squeezing at each other like a can of sardines, Unity is an amalgamation of spread-out users willing to share their experiences and know-how with the game engine and places to upload your new game. It's much looser-knit than the sardines in a bursting-at-the-seams way Roblox can. So, if you're a beginner, being a sardine wouldn't be that bad.
Making It Worth The Effort
Finally, we go to making money. While it's true that many game developers start by being altruistic and putting out games that are free and fun for Dick and Jane, it's just not healthy to keep doing that. Even the gaming forefathers wrote rims and rims of BASIC code to earn a buck or two, and they sure did make way more than a buck or two. Should you finish your mega-immersive game with Unity, you can then indie-style upload it to sites like Steam, cross your programming fingers, and wait for the windfall.
You can also find a publisher willing to take your game in and take care of getting it out to global gamers. How the game will get to its target gamers will be up to you and your smarts and using the support venues and sites to get your play through. The profit may be a lot bigger depending on the site or publisher you decide to have it marketed with.
Roblox, on the other hand, is a one-stop shop. You learn LUA and make your game with the platform's engine.