There are devices that use OOK, on-off-keying to send a signal. There are devices that use amplitude modulation to send a signal. There are devices that use FM or phase modulation to send signals. Each one cannot receive the other properly and decode what is sent.
There are then, devices that use various coding schemes to send the data that are not compatible with other devices.
ALL must match on the transmitter side and on the receiver side in order to communicate.
Paul