Kylian Mbappé didn't learn football on a full-sized field like the ones we have here in Texas. He learned it in a cage. Bondy, a suburb northeast of Paris, is dotted with fenced concrete pitches wedged between housing blocks. The French call them city stades. The games are small, fast, and unsupervised. No refs, no coaches, and definitely no positions. Just constant touches under pressure, against older kids, with a social code that rewards embarrassing your defender.

France didn't produce Mbappé, Kanté, and Mahrez by accident. The Paris suburbs are football's biggest talent factory, and the cage did work the academy couldn't. In an 11v11 match, a kid might touch the ball 40 times in an hour. In a cage? Hundreds. Brazil and Spain run the same play with futsal: smaller pitch, heavier ball, no room to hide a bad first touch. The constrained game overloads exactly the skills the full game is too slow to teach.

Sports science has a name for this: the constraints-led approach. Shrink the space, change the ball, and the environment coaches things instruction can't.

I noticed the same mechanism in my own life before I knew the term. I play a lot of tennis (over a hundred hours a year), and somewhere along the way pickleball snuck into the rotation. It honestly felt like a guilty pleasure until I realized what it was doing to my tennis. The kitchen game is volley training on fast-forward. Points are short, exchanges are rapid, and the low-bounce ball punishes brute force. After a few months of fast pickleball hands, opponents at the tennis net started feeling slow.

Pickleball, of all things, is my cage football. And once I saw the pattern, I saw it everywhere in my work.

The 11v11 problem

My day job is product management on a high-visibility, high-revenue product. It's the full game: big pitch, lots of players, high stakes. And here's the uncomfortable truth about the full game - the touch volume is terrible.

At that scale, a truly consequential product decision comes around maybe a handful of times a quarter. Each one takes weeks of alignment across teams before you find out if you were right - and sometimes you never cleanly find out at all. The feedback loop is so long and so noisy that you can go months without a real rep. You're playing the biggest game there is and barely touching the ball.

Nobody gets good at anything on a handful of reps a quarter. And when the stakes are that high, extra reps are hard to justify.

Side projects are futsal

Nights and weekends, I build small things. A happy hour directory covering a few hundred Austin venues. A photography discovery tool that helps you find the best photography spots around you. A walking app that turns neighborhood walks into a collecting game. None of them will ever be a business, and that's fine. That was never the point.

On a side project I make dozens of product decisions in a weekend. What to build, what to cut, the about page, naming and branding, what the empty state says, whether the onboarding is three screens or one. Then I ship it and find out. The feedback loop is hours (frequently it's more like minutes), not quarters. There's no committee to blame and no analyst to interpret the data for me. Every mistake is mine, immediately and obviously.

That's the cage. Tiny pitch, no ref, maximum touches.

The transfer isn't symmetric

Here's the caveat that keeps this honest: pickleball won't build your serve (trust me, I've tested this). It sharpens hands and anticipation, but full groundstroke mechanics and court coverage only come from tennis. Futsal kids still need Clairefontaine. The French pipeline works because raw cage technique flows into academy structure. Street gives the skill, the academy gives the rest.

Same with side projects. They won't teach you stakeholder management, org politics, or what it takes to change a product that millions of people already depend on. A weekend app has no legacy code, no legal review, no seventeen teams with opinions. The full game is still the full game.

So this isn't a case for quitting your job to build apps. It's a case for playing both games on purpose. The big game gives you scale, consequence, and the hard skills of moving an organization. The small game gives you reps.

Most PMs I know only play 11v11. They're waiting for the job to hand them enough decisions to get great, and the job never will. The math just doesn't work.

Find your cage. Play the smaller game.