The response of the effect is highly interactive with the dynamics of the input signal - this makes it possible to vary the response at will via slight adjustments to playing technique. Therefore, it may take some practice before the response of the auto-wah can be wilfully controlled in order to achieve a consistent sound.
The auto-wah effect reacts dynamically to the input signal, enabling players to modify its output through subtle adjustments in their playing style. It takes time and practice to masterfully control the auto-wah's response for a consistently desirable sound.