It would be hard to conjure up a more contextual discussion IMO; i.e, what is your objective? Are you writing on demand? Do you have to produce a song within a given time frame? I would suggest that if so then all of the discipline approaches here would assuredly facilitate those needs. And then there are folks like us who have no formal or informal music training and write for no reason other than fun. Caveat: I am not suggesting more disciplined approaches are not fun! I just grow weary of reading on some discussions here (not this one) that our lives are incomplete because we don’t know music theory

A lyric notion most often comes to me when hiking or biking or reading. The ideas go into Apple Notes and when relaxed and in the mood I try to work them into a lyric with a genre in mind. Once the rhymes and a semblance of meter are in place I pass it on to Janice. I’ll suggest the genre and often an artist to her. We share a love of multiple genres. She will then get her old Martin box and work up some ideas. She has melodies running through her head all the time. I will on occasion make some suggestions regarding the chord progression. And our admittedly basic progressions spring from our decades of playing bluegrass, trad country and some blues. Well, we are a bit beyond “three chords and the truth.” Most often I never have much of an idea where she’s taken it until recording time.
Pardon the ole guy ramble ... just wanted to mention our approach with zero suggestions that it is the best or the right way - just seems to work for us.
Bud