Because it's annoying being unable to pin down any half-remembered song, or conversation, or whatever.
Me too. In my declining years I'm (very slowly) writing my autobiography, one chapter per address, of which I've had more than 60, plus travel diaries. I want names of people I've worked with, who my neighbours were, friends and foes, highlights and disasters.It's odd but I have a passion for exploring past memories.
I'm probably on my last address now. What a depressing thought.
I look for those half-remembered things, too. They can trigger avalanches of memories.Old TV ads, programs and so on.
On the subject of memories, I have a Toby Jug that dates as far back as I can remember. It used to give a tinny rendition of a tune I thought was Brahms' Lullaby, but has since rusted over. I found the Brahms piece on line and it isn't what I recall...
I don't know how to go about identifying a piece of music I can't play to someone!