The Apple III is actually a pretty interesting machine as far as older 8-bit systems go, and it includes some unique hardware features to work around the limita

The Apple III is actually a pretty interesting machine as far as older 8-bit systems go, and it includes some unique hardware features to work around the limitations of the 6502 CPU: - The machine supports a maximum of 512 kB of RAM. - The 6502 zero-page can be relocated on the fly to anywhere in the 512 kB address space. - Certain 6502 addressing modes can access the entire 512 kB address space without bank switching, where it otherwise would only be able to access 64 kB. - The area of RAM reserved for the operating system and device drivers can be protected from regular apps. - It also includes built-in RGB video at 280x192x16 colors, and a 6-bit DAC for sound. But even without the initial reliability problems the machine probably didn't stand a chance in the market. It fell in the trap of being simultaneously too much computer (too expensive for what it does) and not enough computer (not powerful enough for its rather complicated operating system). And its 8-bit architecture would be quickly eclipsed by 8086 and 68000-based machines, so it was both state of the art and outdated at the same time. Apple was right in that they needed a machine that was significantly more powerful than the Apple II, but their timing was off and the architecture was wrong. The IBM PC did a much better job of hitting the sweet spot of price vs. power vs. complexity.