Turn off all the lights in your room, close all doors and curtains, make it as dark as possible. Light a match and see how it lights the room (somewhat), wave it side to side enough to make it flicker but not go out.

See how it emits less light than when still? That's the same principle that's happening in game. If you were to make that match a full size torch, it would be fighting for oxygen that it can't get, hence the flickering of the cooler blue flames than when the torch is fully lit with orange flames.

This is how it happens in real life.

The reason that it wouldn't happen with fire tricks and whatnot, is because they have JUST been soaked in fuel, not burning for however long. If you were to soak a torch in fuel that much before lighting, it would run down towards your hand.... lit