GoKawiilMy FanCam differs from Samsung's Auto framing feature in one important way. Auto framing adjusts the composition while you're recording, while My FanCam does its work afterward. That gives you more freedom to capture the whole scene first, but it also means the feature can only reframe footage that made it into the original recording.
Imagine recording a school performance, a soccer game or a group dance. Rather than constantly moving the phone to keep one person centered, you can keep more of the scene visible and decide who you want to focus on when you edit the clip later.
It helps to think of My FanCam as moving a smaller frame around inside the video you already recorded. If you're filming several people, keeping the shot reasonably wide gives Galaxy AI more room to reposition that crop as your chosen person moves from one side of the scene to the other. If you start with a very tight shot, there's simply less surrounding image available for My FanCam to use.
The same limitation applies when your subject moves outside the original frame. My FanCam reframes what the camera captured, but it can't recover parts of a scene that were never recorded. Samsung also says the feature won't work when it can't find a subject to track, and it doesn't guarantee tracking accuracy. So for something unpredictable, such as a sports game or a group performance, keeping the person you care about comfortably within the wider shot gives the feature a better starting point.