A story I heard at Sun, which may be apocryphal but was fucking hilarious enough to be a repeatable rumor, was that a release of an early operating system in BETA was determined to be solid and tested and ready to release and ship to customers, so they simply changed the version string from something like "SunOS2.1BETA" to "SunOS2.1FCS" (First Customer Ship), and recompiled. But the change from a 12 character version to an 11 character version threw off the alignment of some important data structures somewhere in the kernel, and the entire OS ran MUCH SLOWER because of 68k unaligned memory accesses!