Sorry, I write so little and short, but I;m overwhelmed with never ending tasks, forgot all about self-marketing :-D So, the majority of profits comes from fat tails of distributions of returns. Miss best X months and you miss almost everything. Problem is they are generally unpredictable* and as a consequence this is probably the biggest drawback of active management, because you can easily catch those best X months by buying and holding.
* At least to my knowledge. You can probably aggregate a lot of data and feed it into A.I., but all edges are small and it can be easily lost when averaging all features.
* At least to my knowledge. You can probably aggregate a lot of data and feed it into A.I., but all edges are small and it can be easily lost when averaging all features.