The Empty Scouting File: A Lesson in Youth Table Tennis Data

In April 2026, when Japan's entire youth competition system shut down because of the pandemic, I sat in front of a forty-page scouting file. Opening it, every page looked like every other page: a trainee's name, a date of birth, and a long blank space where the technical assessment should have been. Forty pages of paper, not a single line of measured data. The person who handed it to me added one sentence: "Take a look, is there anything worth noting?" My answer then, and it has not changed since, was: not yet. An empty file does not say the trainee is weak. It only says we have never looked closely enough. Youth table tennis runs on a paradox. Each rally lasts only seconds, yet judging a fifteen-year-old requires watching dozens of matches across several years. In Japan, the academy systems of clubs and high schools produce thousands of trainees every year. Each has a personal coach, a personal training schedule, and a completely different growth curve. No two of them follow the same path. In Vietnam the picture gains another layer. Youth training centres cluster in Hanoi, Ho Chi Minh City and a handful of provinces with tradition. The number of official tournaments per year is small, the gap in level between age groups is wide, and match data usually exists only as a simple score sheet. When a thirteen-year-old wins a national title, what we actually know is usually just this: she won. We do not know how she won, against whom, or under what competitive conditions. That is why I begin every assessment with a question that sounds dull: what data are we missing? Every brick of data sits on a hidden foundation. When the foundation does not exist, the brick is just a stone suspended over empty space. The job of a player development consultant, put plainly, is to run through nine layers of verification before allowing oneself to write a single line of judgement. The first layer is technique, tactics and equipment. Does the player work away from the table or close to it? Is the backhand a flick or a safe push? Were the rubber and the blade changed during the observation period? A single change of rubber can shift the ball's trajectory enough to invalidate every measurement taken before it. Without that information, any scoring-rate figure becomes meaningless. The second layer is player data and head-to-head records. A player may top a regional event without ever having faced a left-handed opponent of comparable level. The two-year head-to-head record usually reveals more than the ranking table. In table tennis, the win rate against foreign opponents matters more than the domestic rate, because it shows adaptability to unfamiliar styles. The third layer is the event system and points rules. A provincial youth title and a continental qualifying title carry entirely different weight, even though both are recorded in the file with the same word: champion. Skip this layer and a strong local trainee will be ranked alongside an athlete who has already been tested at Asian level. The fourth layer is the competitive landscape. World table tennis still divides into clear tiers: the leading group, the chasing group, the emerging group. A young player raised in a dense competitive environment matures faster than one of equal talent who meets only three opponents in a whole season. The fifth layer is rules and governance. Changes to service rules, to the number of timeouts, or to event formats can overturn the value of a playing style. A small change in ball size alone would rewrite the advantage held by heavy-spin players. The sixth layer is coaching and the talent pipeline. A trainee whose personal coach stays for three straight years follows a different curve from one who changes coaches every season. The age structure of an entire centre matters just as much. If the cohort above is too strong, the younger player is buried on the bench. If it is too weak, that player lacks the pressure to improve. The seventh layer is the risk surface. Wrist injuries, shoulder injuries, body changes during puberty, psychological pressure from being pushed into the senior team too early, each risk needs its own monitoring method. During the pandemic I proposed a protocol of six standardised fitness tests, each repeated three times, cross-checked against each trainee's VO2max data from the previous year. The coaching staff objected. I gave them the figure: seventy-eight per cent of athletes lost twelve per cent of VO2max after eight weeks without competition. Ten trainees were entered into the trial. The eighth layer is media narrative and expectation. A trainee labelled a prodigy in the press carries a form of pressure that appears in no physical metric. This is the most easily skipped layer, and the one that destroys young careers fastest. The ninth layer is industrial transmission. A new playing style at one centre spreads to others within two or three seasons. It affects both the equipment market and recruitment methods. Nine layers. An empty file satisfies none of them. There is a very common misreading of empty files. People read the silence of a document as a verdict on ability. A trainee without careful notes must have nothing special. That reading holds in a perfectly functioning system, and fails in almost every real one. The greatest risk here is a data-supply risk, not a sporting risk. When information is absent, people tend to fill the gap with the cheapest thing available: a highlight clip. That is the most dangerous trap in the trade. Video is only a bone fragment; context is the complete fossil. A thirty-second clip showing a powerful forehand topspin does not tell you whether that player can hold the same consistency in the fifth game, after losing the first two. Cases like Tomokazu Harimoto or Mima Ito are not standards to be compared against, but yardsticks for asking questions. They matured inside a system with an extremely dense international competitive schedule from a very early age, something most young trainees in developing table tennis nations simply do not have. Using them as a reference point while ignoring that difference is a meaningless comparison. I do not write to reject, I write to turn over each layer of soil. If the first layer is empty, the task is not to dig deeper into the emptiness, but to return to the site and measure again from the beginning. An empty scouting file is not a conclusion about a player. It is a report on the error of the person who collected it. Young players are not buried treasure, they are geological strata still being laid down. A layer that has not yet surfaced tells you nothing about the structure beneath it. For youth training centres in Vietnam now building their own data systems, the first question is perhaps not whether this kid has talent, but what data are we missing, and how long until we have enough.