This past weekend, my younger daughter joined a boys team for a tournament. Many of the same players had been together since the winter season several months earlier. Since then, they had attended practices, played games, competed in tournaments, and spent countless hours on the soccer field.
As I stood on the sideline, I found myself wondering about something I had never seriously considered before.
Had they improved?
Not whether they had won more games. Not whether they had scored more goals. Not whether they had finished higher in the standings.
Had they actually become better soccer players?
The more I thought about it, the more uncomfortable the answer became.
I honestly didn't know. And that surprised me.
Perhaps those players had improved tremendously over the past several months. Perhaps they were receiving the ball more confidently, making better decisions, and understanding the game more deeply than they had during the winter season.
The problem was not that development wasn't happening.
The problem was that I had no reliable way to see it.
That realization seemed strange because we live in a world that measures almost everything.
Many families have cameras monitoring their homes—inside and out. Our phones can tell us where our children are at any given moment. Smart watches track our heart rate, sleep quality, daily steps, calories burned, and exercise minutes. Streaming services know what we watch, while our phones track how much screen time we accumulate.
Never before in human history have we had access to so much information about our daily lives.
Yet after an entire soccer season, many parents cannot answer a basic question:
What exactly did my child learn?
We know how many tournaments they attended. We know how many goals they scored. We know whether their team won or lost.
But do we know whether their first touch improved? Do we know whether they are more comfortable using their weaker foot? Do we know whether they scan the field more often before receiving the ball? Do we know whether they make better decisions under pressure?
For many of us, the honest answer is no.
When I was teaching myself English as a second language, I always had some way to understand whether I was progressing. Exams such as IELTS and TOEFL provided benchmarks that helped me understand where I stood and how far I still needed to go.
The assessments were not perfect, but they provided something valuable: evidence of growth.
I knew where I was. I knew where I needed to improve. Most importantly, I knew whether I was progressing.
Standing on the sideline that weekend, I realized I had no equivalent reference point for the players in front of me.
Students receive report cards. Musicians advance through levels and examinations. Martial artists earn belts. Teachers provide feedback on assignments and tests.
In almost every field of learning, there is some way to answer a simple question:
Am I improving?
Yet after years of soccer practices, games, tournaments, camps, and private training sessions, many players receive no equivalent feedback. They know whether their team won. They know whether they started. They know how many goals they scored.
But they often have little idea whether they have become better soccer players.
Most clubs provide information about team performance: league standings, tournament placements, win-loss records, goals scored, and goals allowed. These are team statistics.
But parents are not investing years of their lives to develop a team. They are investing in the development of a child.
Imagine if a school sent home a report card that simply said:
"Grade 7 improved this semester."
Most parents would immediately ask:
"That's great, but how is my child doing?"
Yet this is often how youth sports operate. The team receives a report card. The individual player does not.
As I watched those players compete, I found myself wishing for something similar. Not rankings. Not comparisons. Simply a way to understand where each player started, where they are now, and what skills have improved along the way.
Part of the challenge is that the most important soccer skills are often difficult to see.
Goals are easy to count. Assists are easy to count. Wins and losses are easy to count.
Development is much harder.
A player may score fewer goals than last season while becoming a significantly better soccer player. Their first touch may improve. Their positioning may improve. Their awareness may improve. Their confidence may improve.
Many of the qualities that matter most happen before a player ever touches the ball.
What did they see? What options did they recognize? How quickly did they process information? How often did they move to support a teammate? How well did they anticipate what would happen next?
Perhaps some of the players I watched had improved dramatically in these areas. Perhaps they were seeing the game differently than they had six months earlier.
The problem was not that development wasn't happening.
The problem was that I couldn't easily see it.
As a microbiome researcher, this contrast fascinates me.
Much of my professional life revolves around measuring things that are invisible to the naked eye.
If fecal samples had been collected from those players during the winter season and again this summer, modern microbiome tools could likely reveal how much their gut microbiomes had changed over that same period. We could estimate changes in microbial diversity. We could identify which bacterial groups increased or decreased. We could compare community composition between time points and determine how different their microbiomes had become.
In other words, we could create a detailed picture of biological change occurring inside their bodies.
Yet after months of soccer practices, games, and tournaments, I could not create an equivalent picture of their soccer development.
I could not tell you how much their first touch had improved. I could not quantify changes in their decision-making. I could not measure improvements in awareness, anticipation, or positioning.
The contrast is difficult to ignore. We have developed sophisticated tools to measure invisible changes occurring within the human body, yet we often struggle to see equally important changes occurring within young athletes.
Perhaps the problem is not that youth sports lacks data. Perhaps the problem is that it measures outcomes more often than development.
Winning is an outcome. Goals are outcomes. Tournament trophies are outcomes.
Development is growth. And growth is often invisible until someone deliberately chooses to measure it.
As I reflected on the tournament during the drive home, I kept returning to the same thought.
Those players may have improved tremendously over the past six months. They may have become more confident on the ball and learned to see the field more clearly. They may have become better teammates, developing in ways that will not become obvious for years.
The truth is that I do not know.
And that realization is what started me thinking.
We have cameras to watch our homes. Watches to track our health. Apps to monitor our location. Software capable of measuring billions of invisible microbes living inside our bodies.
Yet after an entire soccer season, we often struggle to see something far more important:
Growth.
Microbiologists spent decades developing tools to make invisible microbes visible.
Perhaps the next challenge for youth soccer is learning how to make invisible development visible.