Why is the observed voltage of the demodulated signal lower than the input signal?

The observed voltage of the demodulated signal is often lower than the input signal due to factors such as signal attenuation during transmission, losses in the demodulation process, and the presence of noise or distortion. Additionally, the demodulator itself may introduce losses, and the filtering process used to extract the original signal can further reduce the amplitude. These factors combined can lead to a lower output voltage compared to the original input signal.