Even with all the technology the industry can muster, people still see colors differently. The challenge was to create a standard where this variation of perception was artificially minimalized.
Consider coffee. It all starts with the same green coffee bean. There are many ways to roast and grind them, and a bevy of brewing styles can produce variations in flavor and strength. The same is true for human eyes. A hundred people can look at a red apple and they would describe its redness in different terms. Is it Red Delicious red or Macintosh apple red? Take a bite and it still tastes like an apple. (Granted people would have opinions on taste, but that’s not the sense we are talking about here.)
The toughest, most demanding standard in the industry was created by THX, the California company founded by film maker George Lucas in 1983. The THX Cinema Certification was originally created to grade the overall cinematic experience at the movies and was later applied to home theatre projectors.