I agree that essentially milking a product with little actual improvement will lead to problems, although it's done Microsoft very well for decades. It helps to have an entrenched monopoly to pull that off. The switch to Intel created more opportunity for the Mac platform than less, so overall that was a win. I don't think anyone should be releasing products that aren't ready, as you singled out OS X which was nearly unusable until about 10.2.
However, Apple had less to lose by gutting their entire hardware and software platform and starting over. Apple also created some very smooth pathways through the migration; 68k code emulation on PPC, Classic environment on OS X, Carbon, Rosetta and a few others. They did the right thing for the long run.
The area where Apple excelled was the iPod and they avoided exactly what you warn against. They released upgrade after upgrade plus several variants for many years in the face of essentially no competition. They captured huge market share, massive brand loyalty and the most illusive variable; trust. Trust was the missing element in all of Microsoft's dalliance with music players. They never had traction and the lack of trust was already spreading to just about every other aspect of Microsoft's business. True to everyone's expectations, Microsoft fucked it all up when they released the Zune and that was the end.