Radio dominated the first half of the 20th century but the advent of affordable TV sets in the 1950s seemed to spell doom for the format. Yet, radio endured. Radio was able to create a distinct image for itself, separate from TV. I have own theories as to why (cars, transistor radios and the music industry) but nothing conclusive.
Cars. For the majority of the 20th century, radio was pretty much the only way to listen to music in a car. That alone was likely enough to keep it economically viable.
IIRC Motorola started out making car radios and the name is motor(car) and the at the time popular -ola suffix for forming product names.