Is local component variable attach to Actor automatically?

I created a simple Actor, there is no thing here, can’t move in scene, that’s ok.

and I create a local variable in Actor’s contructor, compile it again, this component show in ‘Detail’ panel.

ABatteryManActor::ABatteryManActor()
{
	PrimaryActorTick.bCanEverTick = true;
	USceneComponent* sceneComponent = CreateDefaultSubobject<USceneComponent>(TEXT("MySceneComponent"));
}

Yes it is automatically attached afaik to the pivot point of the actor. Looks like you are creating an empty scene component though so nothing is going to be visible in game. Trying adding a static mesh. Also don’t forget to designate a specific component as ROOT component.