I'm struggling to take you seriously as you keep calling it "risk" when it is RISC.
Motorola got into the PowerPC project because IBM had persuaded Apple to switch from 680x0 to a new chip based on their POWER architecture. Apple invited Motorola to join. Apple knew that Motorola had more experience in making single chip microprocessors, but also having two sources gave them more bargaining power.
Actually, that is not true. Andy Hertzfeld gave a talk about the Mac, PowerPC, and AIM which was a fascinating look into what he fighting the rise of Wintel. I don't have time to go into much detail (you can see his talks online anyway).
By the late 80s, everyone knew CISC was a dead end. Apple had developed a secret quad-core RISC chip that was very powerful (for the time) but would make new Macs incompatible with the 68k software base. Sculley was not enthusiastic about this at all (I think because it was a leftover from Jobs and the mac market was pretty soft for this kind of shock by 1988).
Anyway, IBM, Motorola, and Apple watching the rise of Wintel felt this could benefit them all to some degree. IBM had POWER but no real traction, Apple riding a dead end platform, Motorola looking to help fight off Intel. The AIM alliance was a good one.
Apple's move to PowerPC was the right decision but they woefully underestimated how much of a hole the MacOS had put them in. They were never really able to move away from underlying 68k code which hurt the PowerPC performance on the Mac. Look how long (and messy) their nano kernel was.
Running PPC BeOS on a Mac was quite an eye opening experience and really showed how much the MacOS was crippling PowerPC performance.
You know the end, WinTel would be the winner.
If you don't know, Carl Sassenrath (wrote Amiga Exec) worked on Apple's CPU along with some other amazing people.
I apologize, I left out a lot of details but look it up. It is a great story of struggle against WinTel that ultimately failed to be the huge success they were all hoping for.
-P
