Unreal Fest 23: Juice Your Game Mechanics Supplement - Animation Controller and Camera Shake

Hello. I see this:

 # Animation play modes.
    animation_mode<native><public> := enum:
        # Stop after playing the animation once.
        OneShot
        # Reverse direction after reaching the final `keyframe_delta`, then play the animation in reverse.
        PingPong
        # Play the animation in a loop. This requires the animation ends exactly where it began.
        Loop

How to make spawned async loop to play indefinitely?
Why in the example the loop is wrapped around the AnimateProp() function?