Your enemies come from all directions.
The real battlefield is cruel precisely because of this: the mantis sees only the cicada, the oriole sees only the mantis—yet the ecosystem contains much more than just those three.
In real combat, variables are abundant. Your enemy isn't just what's in front of you; it's far more complex than that narrow view.
Investing is a highly professional endeavor. At its core, if you don't treat yourself as the general staff and your capital as your fellow soldiers, you're not qualified to invest.
You're a veteran leading your troops—you go out, and you bring them back. A fund manager's allocated capital is their army; if you can't take responsibility for that money, why would anyone entrust it to you in the first place?