I said it on multiple occasions and I will say it again.
Until Polyphony Digital does not literally inflate the working force, double the employees (from current 150 to at least 300) and establish some kind of EU/US subsidiary-studios that will be solely responsible for collecting the track/vehicle data - all content based updates will be scarce.
Car modeling is a crazy time-consuming job, I will use just example from company that done some outsourcing for Forza 3 here - Austrian
Rabcat worked on preparing car-assets for FM3 > they did
18 exteriors, 9 interiors.
As they state in their official portfolio, it took
14 people a 25 man-months on that task.
http://www.rabcat.com/website2011/media/Rabcat_printportfolio2010.pdf (page 11)
Polyphony Digital have 34 employees working on car-modeling.
Calculate.
Also, car/track collecting data for building them in *premium* quality is a mammoth-job.
We can now all argue about how WE would manage a workflow or whatnot, but at the end it just comes down on one simple fact:
- only real competition in terms of actual content that PD ever faced for the GT series is Forza series. If Microsoft didn't literally spent gazillions in funding T10 for all of their worldwide-contractors and more than 4 outsourced companies that work on car/track modeling, no other game would still be even close to content offered in GT5.
Comparing work by PD and T10 is also nice food for forums but have very little to do with reality. While GT5 is produced by 150 people located only in Japan (thus having limited access to all assets), full T10 workforce is currently probably exceeding 400 people that are working cross-continents in US, EU and Asia.
I do not want to play PD's advocate here, but I can completely understand the lack of many assets in the game.
I have high hopes that some Spec II update will give us plethora of new content - tracks in first place, because after 7 months of constant online play with my friends we're now pretty much fed up with existing track portfolio - bit I wouldn't be surprised if all efforts in PD are now focused on rebuilding GT5 engine into GT6, while some smaller teams are working on almost certain GT for Vita and Tourist Trophy 2.