When you modify a (semi-)complex model and suddenly get a "fillet/chamfer could not be created) it would be useful to know
1) Why?
2) What specific edge it cannot be created on
If you have a fillet command, that fillets 31 edges on a model at least Fusion should make the color of the problem edge(s) yellow so you can see what edge it is and also indicate the place, where there is too little "room" for the fillet, which is not always obvious. Sometimes it is due to a gap or hole in your model, that is not easy to see. To deselect all edges and search for the problem one is pretty much a waste of time, when Fusion already knows it.
This would be (another) great improvement with respect to feedback
