Everything starts with a song.
Your career cannot advance unless you have the songs. If you're a songwriter, you may write them for yourself as an artist or you may write them for other people to perform/record. If you're an artist who does not write you will have to go out and find them - Everything starts with a song.
Without the Songs, you can't have a tour or a photo shoot. You can't talk about producing or marketing or branding. You can't even truly begin to know yourself as an artist, or be able to communicate your unique viewpoint to your fans without songs.
Music is a tool for the heart. Your lyrics open the lines of communication between your heart and the hearts of your supporters.