If you want to change the tires of a car, you can do so without worrying about the consequences of doing so. The average non-electric car is an example of a “complicated system” with 2000 parts. There may be a lot of parts but you can deal with them without worrying about the rest.
The human body, on the other hand, is an example of a complex system. You can’t just change an organ that isn’t working – you need to understand the whole body as parts of the system interact with each other. This is why we talk of the idea of balance with nature’s ecosystems – fixing them isn’t as simple as changing a part. But, when they work, they function as a whole that is far greater than a sum of the parts.
It turns out that learning to identify complicated and complex systems has powerful implications to shipping valuable products too – especially in larger organizations. If we are in a splinter group/”start-up” within a larger organization, we can treat it as a complicated system and just focus on optimizing our silo without worrying about much else.
But, on the other hand, if we are working with an ecosystem of functions and customer offerings, we make far more progress when we take small steps together because the interactions in the ecosystem magnify the impact.
This is why making progress in ecosystems can be slow (and why solving climate change won’t be straightforward). But, when done right, it is far greater than the sum of its parts.