Yes Terry, I have some of those "maybe one day" half-finished poems too! Some will probably never be finished, but like you, I revisit them from time to time and ponder. I work on some, but realise that others were a captured moment in time that is now past and lost. Then I get "great" ideas about potential subjects for poems which never eventuate because I can't find the right angle or trigger. Or someone else says, "You should write about ... " and I mull over it for a while but again, finding the right angle to see it through my own eyes can sometimes be difficult.
Ah, the pleasure and pain of it all!!
Cheers, Shelley