This provided native code which the PPC chip could use without having to access the 68k emulator, while giving users programs that worked well on the 68k platforms. Soon, however, as the base of PPC Macs expanded, some programs were being produced exclusively for the PPC Mac. At first, it was just games where speed added to the experience of game play, but soon other programs began to exploit the speed gains the PPC chip provided. It was at this point that the sun was beginning to set on the 68k Macs. Because, as developers were working to develop new applications for the Mac, Apple's OS developers began to redraft portions of the operating system to help speed the computers along.
Emulators are a bottleneck to swift performance.
Not too long after, the tables had turned, and it was the 68k Macs which had to have new libraries and patches loaded into their systems to make software run. And, all of this work on the Mac OS to utilize the speed of the PPC chip has led to obsolescence. Yes, even in the Macintosh family. At first, the number of Macs which couldn't advance with the latest version of system software was very limited. The Macintosh 128k and 512k, which had made the big leap to System 7 in 1991, couldn't make the cut to System 7.5.