Tried creating a "missing lyrics" smart list, where "number of documents" is less than 1.
It returns zero songs every time, even though some songs have zero documents.
I thought perhaps it was an off-by-one error, so I bumped the threshold to "less than 2" and it returns all my songs.
Are you seeing this in the iOS app, the Android app or the web interface?
Web
This works correctly when I try it. Please provide your account name and the name of a song that has no documents.
account: travisprinziband
song: Starspinning
You haven't uploaded any documents into your account. You are using the built-in lyrics field, which is not included in the count of documents. (Actually it is in the apps, which I'll fix.) To check for missing lyrics, the smart lists would need an option for checking the contents of the Lyrics field, which I'll put on my wish list. Meanwhile, you can look at any song list for the document icon, which indicates the presence or absence of lyrics in your account since you aren't using documents.
Ah, I was confused, since the website lists lyrics under documents when I'm looking at a song. ;)
Yes, that is a little weird. But I figured it was better than adding a separate icon for lyrics.
The web interface now adds Lyrics, Chords and Notes to the list of fields you can filter on -- so you can now make a smart list showing songs with no lyrics (Lyrics equals -empty-) or with lyrics (Lyrics does not equal -empty-). This functionality will also be included in the next version of the iOS and Android apps that I'm submitting this week.