Some call it flywheels, others call it engines, others call it funnel.
David Ogilvy didn't name it in 1963, with the Confessions of an Advertising Man, but the concept was there:
>Why did I write it? First, to attract new clients to my advertising agency. Second, to condition the market for a public offering of our shares. Third, to make myself better known in the business world. It achieved all three of these purposes.
My point is that some disciplines look into have closed concepts, marketing discipline doesn't.
A funnel typically represents the customers' journey, with some amount of dropoff at each step along the way, e.g. discover the site --> sign up --> become active --> convert to paid. And although each step of a funnel leads to the next one, the last step of the funnel doesn't loop back around to feed into the first step, which means the funnel isn't a closed loop that feeds into itself.
A flywheel, on the other hand, is always a closed loop. And most commonly the steps on the flywheel are business strategies, advantages, and activities, rather than steps along a user journey, e.g. provide a wider selection of goods from sellers --> make buyers happier --> get more buyers --> attract more sellers --> repeat.
Just Google Image search a picture of a flywheel and a funnel and the difference should become immediately clear to you. And note that you can combine the two concepts. For example, in the flywheel, the arrow between attracting more sellers and getting a wider selection of goods could be represented as a funnel.
Finally, your David Ogilvy quote is neither a funnel nor a flywheel. It's just a list of three distinct benefits, all of which derive from him writing something, but none of which feed into the others (or at least he doesn't describe how they do.)
Flywheel output less than the input is. Why would we use that word?
As for whether or not "flywheel" is the best term, I think it's pretty good. Yes, real-life flywheels lose momentum due to friction, unless outside force is exerted. But the same is true with marketing flywheels, which is why all of them will have at least one step that requires the injection of outside energy, e.g. bringing in new customers.
Like I'd aid flywheels have always meant energy storage mechanisms that don't reach 100% efficiency.
Marketers know very well what network effects and economies of scale are, and the concept of a flywheel is distinct from either. You can have a flywheel without EoS or network effects, and you can have EoS or network effects without having a flywheel.
Also, it's somewhat pointless to debate what the "original" meaning of flywheel is. Language evolves and changes, and people from one field borrow terminology from others when creating helpful analogies. Terms like "funnel" and "flywheel" are hardly the first to receive such treatment, and they won't be the last.
> Bezos and his lieutenants sketched their own virtuous cycle, which they believe powered their business. It went something like this: Lower prices led to more customer visits. More customers increased the volume of sales and attracted more commission-paying third party sellers to the site. That allowed Amazon to get more out of fixed costs like the fulfillment centers and the servers they needed to run the website. This greater efficiency then enabled it to lower prices further. Feed any part of this flywheel… and it should accelerate the loop. Amazon executives were elated… after five years, they finally understood their business."