Synthetic controls
A synthetic control is an input control that doesn't correspond to an actual physical control on a device (for example the left, right, up, and down child controls on a StickControl). These controls synthesize input from other, actual physical controls and present it in a different way (in this example, they allow you to treat the individual directions of a stick as buttons).
The system considers synthetic controls for interactive rebinding but always favors non-synthetic controls. If both a synthetic and a non-synthetic control that are a potential match exist (for example, <Gamepad>/leftStick/x and <Gamepad>/leftStick/left), the non-synthetic control (<Gamepad>/leftStick/x) wins by default. This makes it possible to interactively bind to <Gamepad>/leftStick/left, for example, but also makes it possible to bind to <Gamepad>/leftStickPress without getting interference from the synthetic buttons on the stick.
Note
To query whether a control is synthetic, use the InputControl.synthetic property.