How about a little experiment?
I'd like you to begin counting. Speak the numbers to yourself or out loud: it doesn't matter. Count out five or six numbers which are consecutive. Now ask yourself, "why did I begin where I began"?
If you are like the overwhelming majority of people you'll have begun counting with the number one and proceeded through two, three, four, five and six. You'll have started at the beginning and worked outward from there. But did you really begin at the beginning? What about zero? Why did you begin at one and not at zero?
One of the great mathematical breakthroughs was developing the concept of zero as a value. In the earliest times the value of zero was represented by the absence of a value in a chain of values. It took time, a lot of time, for the concept of a zero value to have taken hold.
The Aztec's and Greeks appear to have both come upon the concept of zero as a numerical value sometime between 32 B.C. and 150 A.D. with the New World and Old World both laying claim to the honor.
Reading through Wine Spectator and Wine Enthusiast and other wine rating publications I am reminded of the value of zero.
When reading these magazines I see page after page of 80s and 90s with a scant few 70s. What happened to the 10s, 20s, 30s, 40s, 50s and 60s? Are these wine-rating values the equivalent of zero in the pre-Columbian ages?
If Wine Spectator and others rate limit their ratings to a 30 point band between 70 and 100, then why don't they just do so? What is the point of having a 100 point scale where no one scores below 70?
When I was in high school in Greenville, Michigan I had a math teacher who one day explained how the grading system worked. Simply by showing up and taking the test you'd score 50 points. The remaining 50 points were earned by working the problem. So the test was really a 50 point test and not a 100 point test. Never really understood why that was.
So, maybe wine ratings are more akin to taking a high school math test were everyone is given 50 points just for showing up.