Because Bernie Taupin is a lyricist and that is his way to work. He always writes the lyrics to the songs he does and then sends them to Elton or in this case Richie to write the music to them. Read interviews with Richie from last year where he talked about how writing songs with Bernie was strange to him at first because of this modus of working or any interviews by Elton John on songwriting with Bernie for confirmation.

I apologize for it coming across bad I didn't mean it that way. Hey I'm a Richie fan too!