Case in point. I have a poster board in the corner of my office right now that has a bunch of post-it notes on it. Each post-it has a title of a play that I think I "should write". Have I written any of them? Nope. I have the ideas but I never get them out because yeah the ideas are funny but I found out that good ideas are never what brought me to the keyboard with a play that I just had to write. What does get me writing is causes, injustices in this world, or that nagging tug in my heart that says "you HAVE to say something about this." I wrote the entirety of 27 Days with my heart tugging me along for the ride, spurring me on to write just one more scene each time.
I found that the greatest plays you write will be the ones that, while they feel like a prizefight to get them out of your heart, are the easiest plays for you to get on paper. I found that there are some plays that are just super easy for me to write, as in the don't require me to think and I can just stick to my heart and let it decide. My best plays have come about when I leave my brain out of the equation until the revisions come around.
My gf, in all her wisdom, summed it up earlier this year. She keeps saying that "Causes are your Muse". I have to have a protest song to sing an oppressed face to give a voice too. Or sometimes I have to have an overlooked character whose soul is screaming out to me "I need to be put onstage, please let me out!" It's my heart that makes such a great writing companion in the first stages. My brain gets to play later when the revisions start.