I don´t know anything about Naughty Dog, but for Rockstar and GTA5 they, as a company had more than the GTA5 project running at the same time. How it normally works is that you start up the project with a small group of designers, writers and architects (software architects not house
). When they have made their first drafts, you might add som QA people and testers and lead developers. When the first drafts are done then you can start adding more people. When you get the complete framework up. (Story, game mechanics, layout of graphics areas, list of vehicles, etc) you can add a lot more to basically add the flesh. Then when the bulk is done you remove parts of the manpower and only keep those needed for polish and release work.
If you are working on more than one title, as a company you can optimize your work effort.
It can be dangerous for an organization to only focus on one thing because you might end up as:
- Path dependant; you choose the same solutions time after time, even when the world have moved on and it exists better ways.
- Bug blindness: because you see the same thing over and over, this have happend to me several times. I have been working for a long time on a feature, and have polished it perfectly, then a colleague looks for it for 2 minutes and says something like "WTF man, this will not work because..." and sees something I got blind to.
- Endless polish on the wrong thing: you can end up using a lot of time making something that basically the users don´t want but you have so much time on your hands and only working on one project.
Project often follows the S-curve where you often add more people in the steepest part of the S.