Even as baseball fans and those within the industry gain a deeper understanding of statistics, one number remains largely misinterpreted and misunderstood. The elite post atop the traditional 2-8 (or 20-80) scouting scale, the 8 represents the territory so far to the right on the scouting bell curve that few scouts dare to tread there. It represents only the most elite of tools and should always be respected.

As a young scout learning the ropes in the mid-2000s, I didn’t immediately understand the significance of this extreme end of the scouting scale. But gradually, my respect for it grew as I began to understand its scarcity. In 2012, I watched countless games from high school to the pros. I spoke to scouts and industry insiders at all levels of baseball. And only very rarely did I hear mention of an elite-level tool.

Given the nature of scouting, elite grades are most often placed on fastball velocity and running speed. These are the only two traditional scouting categories that offer a standardized, empirical measurement-based scale by which grades are assigned. Pump your fastball consistently in the 97-plus-mph range, and you’re going to get an 8. Get down the line to first in less than 4.0 seconds from the right side (3.9 seconds from the left), and you’re going to get an 8.

The benefit of such a scale is that the risk of tossing around bold grades evaporates. But when grading all other tools, evaluators aren’t afforded that luxury, which makes the 8 grade far more nerve-wracking to commit to.

For the past couple of years, Billy Hamilton’s speed has fascinated us all. He’s raced to first fast enough to make stopwatches explode and routine groundballs become an adventure. Hamilton deserves something better than the top of the scale. He breaks the scale.

When I discussed players with scouts last year, two others were routinely cited as having legitimately elite speed: Toronto’s D.J. Davis and Philadelphia’s Roman Quinn. Of course, burners are relatively easy to find, and there are additional players with 8 speed in the minor leagues. But none was mentioned with the frequency reserved for Hamilton, Davis, and Quinn.

Elite fastballs are not as common as elite speed, but they are just as easily quantified, and players who possess them can be found in any season. While players like Gerrit Cole, Carlos Martinez, Trevor Rosenthal and others may reach the elite levels of the velocity scale at times, earning the occasional future 8 grade, no player exhibits extreme velocity like Detroit’s Bruce Rondon.

Rondon’s velocity is so consistently exceptional that I could select nearly any outing to highlight. I could discuss his famed showing in the 2012 Futures Game, or any of a dozen amusing exchanges with scouts after they saw him pitch for the first time. Instead, I want to explain what I saw in early August, the last time I saw Rondon live.

Entering the game in the ninth inning, Rondon threw 11 pitches; only five were strikes, but that’s not what’s important here. In those 11 pitches, he pumped eight fastballs with the following velocities: 98, 100, 101, 101, 99, 100, 102, 102. My gun isn’t hot, I promise. That, my friends, is an 8 fastball if there ever was one.

This is the point at which we exit the soothing confines of the shallow end of the pool and enter the murky waters that can make an evaluator look like an idiot. No longer do we have a defined scale to fall back on. Instead, we must venture into an abstract realm where observations and opinions can vary like the New England weather. This is where scouts get uneasy about putting 8’s on anything.

Elite power can stand out in any crowd, whether in batting practice or in game situations. It tends to be obvious. It also tends to be quite rare in today’s game. While scouts will occasionally mention players like Joey Gallo as having the raw potential to reach the heights of 8 power, rarely in recent times have we seen a stretch with so few classic power prospects.

There was only one viable name that came up last year as a candidate for 8 raw power: Minnesota’s Miguel Sano, who has immense raw. In the opinion of several front office officials I spoke to, Sano’s truly elite power stands alone in the minor leagues.

Defensive evaluations also struggle to reach the far right of the scouting scale. Not a single outfielder received present or future 8 scores from the scouts I spoke to last year. Similarly, not a single catcher earned an 8 for his defense. In fact, only San Diego’s Austin Hedges received a mention as a player with a remote chance of achieving such a score at some point down the line.

Among infielders, only the incomparable Jose Iglesias earned elite marks for his ability to flash the leather. His defense reminds scouts of Rey Ordonez. The only time scouts stop discussing his defensive prowess is to mention how weak his bat is, before quickly jumping back to the discussion of his almost pornographic defensive abilities.

Classically elite arm strength—like that of Shawon Dunston and Raul Mondesi—can also stand out in a crowd. Few arms in the minor leagues can reach such levels. Aaron Hicks’ name comes up on occasion as having an elite outfield arm, but that opinion is hardly held uniformly across the industry. Cubs infielder Junior Lake has an almost unanimous 8 arm, with some scouts suggesting he should move to the mound if he doesn’t hit enough to pull off a big-league career as a position player.

A player I’ve had ample exposure to, Detroit shortstop Dixon Machado, teeters on the precipice of owning an 8 arm. His slight frame can fire lasers across the diamond, and after watching a sequence of his throws during instructs last year, I engaged several scouts in a discussion of whether or not Machado’s arm warranted the rarest of rare grades. In the end, despite dissenting opinions from some of the other scouts in attendance, a few of us retained the belief that his arm was in fact elite. These are the murky waters I previously discussed, and we haven’t even approached the good stuff yet.

For many scouts, elite hitters don’t exist at the minor-league level; not as a projection, and certainly not in the here and now. Last year, for the first time in my career, multiple scouts were bold enough to suggest that a minor-league player might have the potential for a truly elite hit tool. Each of them, with a healthy dose of hesitation mixed in, squeaked out the name Oscar Taveras when the subject came up. That’s a seriously bold statement and one that led to open admissions of uneasiness when brought up with the BP Prospect Team.

A true 8 isn’t just the best tool relative to those of other current players—it has to stand up to the best of the best across the history of scouting. For that reason, not every tool will be represented in an annual survey of this nature. Given the variable nature of player development, a tool that previously rated as elite might not even sustain that designation the following year. I’ve made no mention of outfield defense, command, curveballs, sliders or change-ups in this discussion, because no player rated an 8 in those areas despite inquiries devoted to each.

We don’t get to live in the rarified air of elite tools. We only get to visit on occasion and cherish it while we have the chance. So don’t get discouraged if your favorite player isn’t mentioned as having an elite tool or elite potential. Instead, remember one rule: respect the 8.

Special thanks to Jason Cole, Chris Mellen, and Jason Parks for their contributions to the discussion of elite tools.