Can we detect effusion? Coin flip confusing

[DrJonnyT]

I dont really understand what this coin flip is about- ar we trying to say that the worst case scenario is just flipping a coin, so our model but at the very least do better than that? Or is it about whether we as humans can look at an image and tell if it's effusion?

Flipping a coin is confusing, when you are actually just choosing a random image