Why doesnt Microsoft invest in there own studios and exculsives?

[dsister]

Microsoft has been starting up a few development studios just recently. That doesn't mean they are instantly going to start putting out games...

They own:

1. Big Park
2. Rare ltd.(two studios)
3. Lionhead
4. MGS
5. Firebird
6. Spawnpoint
7. Turn 10
8. Wingnut Interactive

Now we have only seen games from:

1. Big Park
2. Rare ltd.(one studio)
3. Lionhead
4. MGS

So they still have four(five) development houses that should be working on new games.