Because people grow up, well, most people anyway.

I'm sorry, but until the original post is worded like a design philosophy question, I'm going to struggle with treating it as such. I can guess what you are trying to ask (How do I design X for replay value?), but it's so vague I could well end up answering a bunch of things that you don't care for.

I very nearly moved the topic to Community when I first read it, because of the wording.

Something I learned while people were playing Generiquest was, people get bored when they have nothing to do. Also, regardless of how fast you work, people can always play anything you make faster than you can ever make it.

Once people run out of things to do, they are stuck with grinding on some way, shape or form. Whether that is getting stronger (by killing stuff), or collecting items (by killing stuff, or making them) they are grinding. And people get bored of doing the same thing over and over and over again.

People will ALWAYS get bored of a game, and there is nothing you can do about this other than continually add new stuff to it. Even then, people will still get bored of it, because it is just impossible to add new stuff to a game faster than people are getting bored of it.

The only advice I can give is this.
Before releasing the game make sure it has a lot of stuff to do. I'm not talking about a few hours, or even 10-20 hours. I am talking about 100-200 hours at minimum. 100 hours might keep a person of average intellect entertained for maybe... 2-3 weeks.
Secondly, I would advise you set up and make the game in a very efficient way. As efficiently as possible, and set up systems and methods that reduce the time it takes to add new things to as short as possible. The quicker you can add things, the longer it will take for people to catch up to you, and the longer they will be entertained.
Also, though it is not always possible (especially for games like RPGs), try to add as much replayability to the game as possible.

Anyway, from what I have seen of your game Sigma Metaverse, it is basically one huge grinding game. The objective is to make items, so you can make more items, so you can make even more items. And it is executed in a very dull way (click on a button, then wait a few minutes, and repeat this each time).
The item creation system is done in a very dull way, and outside of that I saw nothing worth doing. There was no interesting storylines or quests to involve myself in, no unique locations/dungeons for me to explore, no challenging puzzles to pit my witts against, nor was there any particularly dangerous foes which required me to devise an ingenious strategy and then fight to the death against.
Make the games item creation system more involving and fun, and then add everything I listed above. That way, people wont get bored of the game as fast.

thanks kindly.

I was only in the origins stage, but just added 'Chapter 2'.

There is a plotline, but it's weak at first. Look in tutorial for it.

It has reached the 'discovery' stages of the rpg.

It is fine and dandy saying you'll do, or have done these things. But most people do not care about what you say, they want to see what you have done, if they cannot see you have done it, then for all intents and purposes it might as well have not been done.

The "storyline" in the tutorial. All you are doing is telling them there is a storyline, but they cannot take part in it, and infact they cannot see it at all in the game. I doubt anyone even cares about it, simply because they cannot take part in it in any way, shape or form.
Until you start adding a storyline in the game that people can actually play then your storyline is not something that will attract or keep people entertained at all.

Ignoring all the math you tried to do (which makes no sense at all!) all those games you listed have one thing that determines how long their playtime is, and that is replayability.
Simcities playtime before you get bored of it isn't determined by how much content it has (which is what I was talking about), each time you play the game it is in someway different, which is what makes it replayable.

Also, from what I learned, adding "new game mechanics" (in my case, new character classes for people to play with) added very little replayability to the game, since people were still playing the same things, just in a minorly different way. Even when those classes had entirely new mechanics that no other class had, and led to interesting strategies during gameplay.
I found that adding new classes, items, abilities and so on didn't keep people entertained for very long (for the amount of work put in). But adding new dungeons, quests and bosses had a much greater pay off in how long they would keep a player interested (for me it was about 10 hours of work, translated into just over 1 hour of playtime for things like dungeons/quests).

This isn't always the case, but in any game that relies heavily on content and stuff to do, it will almost always take you a lot longer to make stuff than people can play it.

In a persistent game, a character class tends to require grinding through the same content again. Classes are mutually exclusive, but they can all experience dungeons, quests, and bosses. It makes sense for developers to focus on content for the widest market instead of content which players may feel costs too much time and effort.

In a session-based game, players just pick their new pieces during the next match. Scenarios (which could be the analog of dungeons, quests and bosses) tend to be mutually exclusive, but the pieces can be used in all of them. It makes sense for developers to focus on content that players can, with minimal effort, use throughout the game rather than content which is only valid during a particular session.

Find out what makes people want to play your game and add more of it.

I checked it out because of the promise of choice. Your Creations post stated you could find the Demon King and kill him, or not. I liked that 'or not' option. Actually, just having the option was enough to get me interested.

Then I saw all your item creation stuff, which took forever to figure out, and that got me interested in seeing what neat things there were to make. After a while, I got bored with making things and getting killed by monsters.

If there was more of that story around, and more choices to be made regarding our place in the story, I'd probably have stuck around longer. I like the concept, it was just a little too thin in the "stuff to do" dept.

Developous wrote:

Sometimes a game becomes to boring for some or another reason. Perhaps it's too mundane, perhaps it just lost it's flare.

This is a post to discuss WHY some games, even great ones, become too boring after a while.

I think a lot of it is predictability. A game gets dull when you know where all the quest givers are, what the best items are, and when you could almost literally draw a map of enemy spawn points. Every game suffers from this unconditionally, the only variable is how long it takes.

This is an incredibly broad subject touching on the elements of Game Design.

What you need to do is to not take The Magic Mans advice. What works for one game doesn't necessarily work for another, and solving 'boredom' isn't a question that you can answer per se.

Not having fun is the end result, something a player arrives at through the rest of your game. A few things to take into account, some of which has already been touched on here:

* Content creation (if worth a dime) without artificial roadblocks takes anywhere upwards of several hundreds of times as long as it will take players to complete said content. Think of MMORPGs which take months developing new dungeons, some of which (most in fact) are completed in less than 2 days.

* Artificial roadblocks come in various shapes and sizes. They're also called timesinks. The important thing here is that timesinks aren't necessarily bad, it depends on how they're applied. A simple timesink which most games today have is experience/levelling - You don't instantly level each kill, you have to kill several things. Through a combination of difficulty and time taken, players will usually feel a greater sense of accomplishment if it took work to get somewhere. The key to this is to find the balance between necessary/unnecessary, as well as too much / too little. This is something most all games get wrong and subsequently tweak periodically, because its very hard to find a happy medium.

* You should be planning for both casual and hardcore players, unless you very specifically market your game to a narrow target audience. This isn't only about saying, 'This game is for casuals' or 'This game is for hardcores'. If you're marketing to a very specific audience, the entire game has to take that into account - Every feature/decision/part of the game. If you're marketing to a broad audience, the entire game has to take that into account as well.

* Never implement a feature 'just because', 'because game X has' or 'To punish players'. There is a secret to punishing players without them getting so pissed they drop the game: It has to make sense, it has to convey a feeling of fairness (Random punishment is *never* good unless it is within the scope of humor and is harmless to the player) and it has to be predictable. There was a MUD that had death traps (Rooms that you entered and simply died on entering) with no warnings around, that shifted location randomly. Needless to say, that feature was very unpopular. Another MUD had deathtraps in specific locations and context-hints in surrounding rooms to warn you - That was fine.

* To extend on the above: Your game has to make sense as a whole and this is something many new / young developers forget. You can't simply mix and mash features from random games because the features worked for that game. You'll end up with a game that makes no sense and isn't fun. To help with this, companies (and indie developers alike) often come up with general 'goals' for the project to always keep in mind. A set of golden rules perhaps, that all features HAVE to abide by. This is a way of mentally restriccting yourself from wandering off the road, so to speak.

Some easy ways to make a game boring, to bridge from the theorycraft above:

* If the primary focus of the game is combat and combat is dull, the game will by extension be dull.

* If the game tries to push exploring as a primary element and the rest of the game doesn't carry that, the game will be incoherent/dull/meaningless.

* Making players travel long distances to reach 'fun areas', with the long distances filled with 'not fun' things or waiting - Thats not fun. Keep in mind what distance does: It does increase the percieved size of the world, but if the majority of said size is filled with uninteresting, dull, repetetive terrain then that size is just wasted.

* Making players jump through 'not fun' to get to 'fun'. This is a very common mistake. This is usually done to keep players in the game longer, but this is the WRONG type of timesink. Never intend on making players do something you know is full of 'not fun'.

These are some small pointers. There is such a huge amount of things to take into consideration when you ask this sort of question. If you had an end-all answer to this, I'm sure you'd be rich pretty fast ;) In the end, its about entertainment, tolerance, psychology (both game to person, and person to person), a little bit of luck, stereotypes and more.