My fiddle leaf fig drops a leaf once per ~1.5 months. I am puzzled about whether I am overwatering it, underwatering it, or something else is wrong. I am attaching a picture of the leaf I found today.
I purchased it 9 months ago. It is actually 3 independent trees in one pot. It was repotted 4 months ago (it had no particular issues following the repotting). It stays by the window where it receives mostly indirect/low light (I tend to keep blinds partially closed during the day). I water with approx. 1.5 cups of water every 3 days (subject to variability, I am not very systematic about it). In the past 2 months, it has generated 2 layers of new leaves (each of the 3 independent trees produced 2 layers, each layer consisting of 2-3 leaves) which I have been taking as a sign of adequate watering/overall care, but the occasional leaf drop keeps bothering me.