THE IDEA
The shape of how things grow
Almost nothing grows forever. And almost nothing that grows does so at a steady pace. The real shape of growth - in nature, in markets, in skills, in movements - is an S.
It starts slow. A new idea finds its first few supporters. A business gets its first customers. A plant pushes its first shoots through soil. Progress is hard-won and barely visible. This is the bottom of the S, where people get discouraged and give up because nothing seems to be happening.
Then something catches. A reinforcing loop kicks in - word of mouth, compound interest, network effects, confidence building on confidence. Growth accelerates. The curve sweeps upward. This is the part that feels like magic, the part everyone wants to bottle and repeat. But it doesn’t last, because eventually the system hits limits. The market saturates. The easy gains are taken. The soil runs out of nutrients. Growth slows, flattens, and levels off at a new plateau. That’s the top of the S.
The reason this matters is that where you are on the S-curve changes what works. Early on, the challenge is persistence - keeping going when progress is invisible. In the steep middle, the challenge is managing the speed. Near the top, the challenge is recognising that the current S-curve is ending and the next one needs to start. People misread their position on the curve all the time, and it leads them to apply the wrong strategy at the wrong moment.
IN PRACTICE
Slow, fast, then flat
Learning a musical instrument follows a classic S-curve. The first weeks are agonising - your fingers hurt, nothing sounds right, progress is invisible. Then something clicks and you improve rapidly. Songs start to come together, muscle memory builds, each practice session produces noticeable gains. But eventually you hit a plateau. The easy improvements are behind you, and further progress requires a different kind of effort - deeper technique, subtler skills, more deliberate practice. The curve has flattened. The strategies that worked in the steep part (just practise more) stop working at the top.
Smartphone adoption followed a textbook S-curve globally. Slow uptake in the early 2000s, explosive growth from roughly 2010 to 2018, then a levelling off as most adults who were going to buy one already had one. Companies that were built for the growth phase - selling more phones to new buyers - had to fundamentally rethink their strategies when the curve flattened. The market didn’t disappear, but the dynamics changed completely.
Social movements often surprise people with their speed because observers only notice them during the steep phase. A campaign for policy change can work quietly for years, building support one conversation at a time. Then it crosses a threshold and seems to explode overnight. Commentators call it “sudden” - but it was an S-curve all along. The slow early work was building the conditions for rapid change. The lesson: the invisible phase isn’t wasted time. It’s the foundation the steep part stands on.
WORKING WITH THIS
Know where you are on the curve
The first question is always: which part of the S am I in? This changes everything. In the early flat phase, the right move is patience, experimentation, and not judging progress too harshly. In the steep phase, the right move is investment, capacity-building, and riding the momentum. Near the top, the right move is starting to look for the next S-curve before the current one fully flattens.
The most common mistake is assuming the steep phase will last forever. When something is growing fast, it’s tempting to project that growth into the future indefinitely. But every S-curve has a ceiling. The question isn’t whether growth will slow - it will. The question is what the ceiling is and how close you are to it.
The second most common mistake is giving up during the early flat phase. Most S-curves look like failure before they look like success. If you’re doing something new and progress is painfully slow, it doesn’t necessarily mean the idea is bad. It might mean you’re in the bottom of the S, where growth is real but not yet visible. The hard part is knowing the difference between “this is the slow start of something real” and “this isn’t going to work.” There’s no formula for that - but understanding the S-curve shape at least gives you a framework for the question.
THE INSIGHT
Three curves, three mistakes
The S-curve has three phases and each one tempts you toward a different error: giving up too early in the slow start, overcommitting during the rapid middle, and holding on too long near the flattening top.
RECOGNITION
Knowing it when you see it
You’re on an S-curve when early progress is frustratingly slow despite real effort. When something suddenly takes off after a long quiet period. When growth that felt unstoppable begins to decelerate and people can’t figure out why “what used to work” has stopped working. When someone says “we just need to do more of the same” but the curve has already started to flatten - the same inputs no longer produce the same outputs.