Game Life

The amount of time it takes to finish could well be irrelevant to whether it's a good game or not.

Hopefully more than an hour?

Your question is too general. What type of game did you have in mind?

I don't think there is a useful answer anyone can give to this question. Even if you specified a genre. It's like asking "How long is a piece of string".

Perhaps it would be more useful to tell us *why* you need to know this. If, for example, you are planning on making an indie game and are trying to work out how much content you need to put in, then someone might be able to offer you a useful answer.

Your guess Sandman is right.
My idea is to make a game who fights forest fires with a helicopter.
I am developing the gamedesign document and learning the techonologies for make it.
The games i found who was similitaries with my idea are simcopter and gta san andreas. They have a lot of content, much more than a indie can make.
I want to have a ideia about the quantity of content needed for make profit selling my game via shareware.
Thanks for your help.

In that case, there are a few questions you may have to ask yourself.

"How much content can the gameplay support?"
A game can definitely be too long. If a player gets bored before finishing the game, that's probably too much. Ideally, you want to leave them satisfied, but wanting more.
Of course, different players will have different tolerances. Personally, I found GTA:SA to be far too long. Every so often, I pick up from where I left off, play through a few more missions before getting bored and moving on to other things. I've been playing the same game since it was released, and I still haven't got past the second island [grin]

"How much content do I need to give a satisfying experience?"
Again, this will depend on your gameplay. Many people complained that Portal was too short: I completed it in a single evening. However the gameplay was extremely engaging, the storyline entertaining and the whole experience left me satisfied.

"How much content can I afford to make?"
This is probably the hardest question, and ultimately, the most important, because it will affect the success or failure of your game design.
Consider the gameplay/asset ratio of your current design. If you require a large amount content for a handful of hours of gameplay, then it will be very difficult to make the game profitable. Big, story based RPGs with large detailed and interactive worlds have a low gameplay/asset ratio. Even big developers with large budgets have to cut corners to keep the asset budgets down to something manageable, which is why you see so many cookie cutter NPCs, buildings, etc. in these kinds of games.
On the other hand, games with randomly generated levels (e.g Diablo II), ever increasing difficulty (e.g Tetris) can offer effectively infinite gameplay with fairly limited assets.

As an indie developer, unless you have money to burn and can employ legions of artists to create content for you, with no care as to whether you make a return on your investment, you will need to make the most of your resources, and that means squeezing as much gameplay out of minimal assets as you can.

Thank you a lot Sandman, your post was very usefull.
You don´t need but you deserve to be rated up, so i rated you up :).
One more question, what sites or books give me more precisely information about this topic?

Thanks again.