[imtringued]

It is not a metaphor if you think the Fed is applying control theory to regulate the economy.

But some people take it too far and think if there was no Fed there wouldn't be any oscillation. That is not true. Bitcoin also "oscillates".

Oscillations happen because of a time lag that leads to an overshooting of the target which then leads to overshooting on the way back and so on.

The economy never becomes perfectly stable but there is no rule that the oscillation can't be smoothed out until it is no longer a problem. We aren't that far yet.

[xapata]

Calling it an "oscillation" means that you know the causal mechanism has a spring-like behavior, which is a more complex model than a random walk. A random walk can easily appear to be an oscillation, but is not one.