Hey Randy
It depends on the function of the lyrics. Some lyrics the main function is only to convey emotional snippets that compliment the melody and arrangement, others deliver a message, others tell a story. Sometimes the lyrics are the most important component of the song, others again they are playing the supporting role. So....
What makes good lyrics?
Memorability
Suitability to purpose
Ability to evoke suitable emotion(s). Often an emotional journey.
The integrity of the lyrics (emotional, themeatical etc)
Connectability, accessability
Good lyrics also tend to show the singer in a good light, even in protest songs!
More contentious is the fact that it doesn't matter how good the song is if no one knows about it so... I'll add:
A good quality, effective promotion campaign
Fundamentally fans need to want to listen to it, over and over again... and want to share it with other people. That is only achieved when you have all of the above.
And for longevity:
Subsequent, periodic promotion campaigns
A fanbase