From one of the deepest research firms and strongest proponents of modern quantitative approaches - Alpha Architect - https://alphaarchitect.com/2022/02/01/what-explains-the-mome…
We walked away from the question and determined the following:
We will never really know why the momentum factor actually exists. But we know that is does exist and it is arguably stronger than value.
The arguments as to why momentum exists can be boiled down into two primary camps:
momentum is an underreaction phenomenon
momentum is an overreaction phenomenon.
Our most informed guess is that momentum is driven by underreaction and this is best captured via the so-called ‘From-in-the-Pan‘ algorithm, which we use in our own investment processes — i.e., Quantitative Momentum. https://alphaarchitect.com/2015/12/01/quantitative-momentum-…
Oversimplified, frog in the pan implies gradual sustained price changes, not sudden.
https://alphaarchitect.com/2015/11/23/frog-in-the-pan-identi…
The conclusions are clear: a more sophisticated momentum strategy that focuses on the path-dependency of momentum generates a much stronger momentum effect.
Worth a deep read and further discussion, IMO.