Your'e on crack.

http://en.wikipedia.org/wiki/Naughty_Dog

Read the first line.

In SSJ12's world, Unreal Tournament 3 is the best selling FPS ever and every second party developer for Sony is a willing participant.

Mostly anyone (developer) who is subject to a takeover may be "forced" into doing sequel. Either they may have to make a sequel to a series that was financially good (which is unlikely since they were subject to a takeover in the first place) was meant not to be followed up, or they may have "revive" an old series or make some kind of retro tribute half-ass version of it.
The most common scenario, I think, is that after a takeover or a merger, some dev's might be coerced into taking turns and making changes in their sequels that they may be opposed to at the core (I know this happened to some Westwood programmers when EA wanted the first, new Command & Conquer after the buyout).

Making new IPs is risky and most companies are adverse at taking risks.
It is a huge investment to develop a new IP too but it can be successfull.

A good example is AC, a totally new IP that has sold over 5 millions copies over both HD consoles...

For the sake of laughter I'll agree with you. I'm sure Nintendo regrets making Pokemon, Mario, Zelda, Smash Brother, and Metroid games :/ They must wake up every morning, and pity going to work. Such brilliant minds being wasted. Sigh.

Franchises not only make money, but they can be a blast to work on. Ever hear developers mention that they couldn't get everything they wanted to in a game? I sure have. I hear it every time a game is released. Besides for the sake of creative freedom, sometimes it's just good to expand. Plenty of company's make plenty of I.P.'s, and the public doesn't always take to them. On a business and creative aspect, franchises can be a blessing. Ask Sega about making millions of I.P's.

I don't know what you do for a living but myself... I would not be happy with some of the end results Sega is coming up with if I was part of that team as I take pride in my work.

On a side note...

Why was RE4 great? Because it was a risk and a new direction, it breathed new life into the series. Now this doesn't mean that the prescription to keeping a franchise fresh is doing something completely radical or that staying the course is harmful, but its clear to see when developers are too timid to tamper with the formula.

Call of Duty 4, while a sequel in much the same regard as many of these mediocre titles put war in a new template of time and location as well as innovated online co-op and gameplay. It was a subtle balance of improvement and innovation. But unfortunately for most FPSs they're stay good only so long as something better doesn't come out.

I see where your comming from, it just makes me wonder if you've ever played any of those games that you just wish didn't end yet. Doing a dead end job does suck, but the series's can find innovation like you mentioned, they can implement new ideas, they can expand.

I mean I've seen Ratchet and Clank from the first build to the newest one, and needless to say it has progressed ^^ and it still feels original to me. Which is proof that you CAN crank out a new installation every other year and still have it be vibrant, you just have to be a good developer lol.

And games like Final Fantasy, they carry the same name, but they all feel different when you play them. A franchise by name, not by feel.

ChronotriggerJM

I've played many games that I didn't wish had an end. Some that come to mind are Sonic 1-4, Resident evil 4, Castlevanie:SOTN...also, I agree there are companies that can pull off great sequels evey 2 years (Insomniac for example...very talented studio). People love and will always love great sequels...

Here is an idea...someone should start a post of sequels that weren't necessary and should not have been made. Not me tho...I'm not the type that enjoys geting roasted...plus I don't want to lose any more credibility in ssj12's eyes.  :)

 1. Half-Life 2 is better

2. Counter-Strike is better

3. Quake is equal to it

4. Sony could rot for all I care