Several days ago, I decided I wanted to write lyrics for a song, but I could not think of an idea. So I figured if I tried free writing an idea would just show up. But when I was free writing, nothing I wrote was a candidate. The exercise did not lead me anywhere. I feel as though my brain is not able to come up with song ideas, either because I don't have enough world experiences or because my cognitive skills are deficient. Because of this, I procrastinate chronically, and never put effort into forming an idea. I don't know why it is so difficult.
Trying to write something without knowing what you want to write is a bit like wanting to fall in love before you actually meet someone. A classic case of putting the cart before the horse. I believe the most promising sequence is: 1) idea, 2) decision about what best suits the idea (song, short story, epic novel), 3) begin to write. Best of luck.
I never really know what I'm going to write before I start writing. It's just how I work. But I can't say I always get it right. You had one writing session that didn't go anywhere. I'm sure we've all been there. The thing is you have to keep doing it. It might take two tries. It might take two hundred. You say you are procrastinating and not putting in the effort. Well, that's not going to get you too far. Seriously, are you really questioning why your writing isn't going well when you admit to procrastinating and not putting much effort into your ideas? Writing requires both effort and practice. If you work at it, you'll get better.
I have days when I seem to write a sentence then hit delete, over and over again. It doesn't mean my cognitive skills are lacking, just that it's not a great day. I doubt there is a writer alive that hasn't been there. Writing takes work, effort and determination. It's not just going to all fall into place becausevyou decide you want to write a song. I would suggest paitence and practice. And don't get down on yourself when it doesn't go well, just keep at it.
If freewriting doesn't work for you, don't do it. As for ideas, I promise you that you have thousands and you're just being very critical of yourself. Don't be. It's not about ideas. It's about the execution. The lyrics to one of the best songs of all time are at times rather silly: I see a little silhouetto of a man, Scaramouche, Scaramouche, will you do the Fandango? Thunderbolt and lightning, Very, very frightening me. (Galileo) Galileo. (Galileo) Galileo, Galileo Figaro Magnifico-o-o-o-o. Just write whatever you feel like, rewrite, get feedback, rewrite again, try and try a hundred times more.