Nice looking box Yes finishing is probably second only to form for the most important factor Well i count sanding as a part of finishing If a piece isnt sanded to perfection then it should be intentional and obvious to tbe viewer Other than that you should never see any sanding marks And it gets harder and harder as we get older and cant see 😂
Ditto what John L said. I probably spend as much or more time preparing and finishing the surface as turning. Much of my sanding is by hand with the lathe off to avoid circular scratches. I like multiple small "almost point source" lights for both turning and sanding to better see the curves and scratches - far better than broad, even, diffuse lighting. I sometimes rub a cloth with naphtha on the wood which might show scratches better.
Now it makes sense. Couldn't tell scale from the photo -- could have been 12". ;-)
Boxes are fun. I need to make more myself. I asked because I made a slightly larger one (6"), using the traditional approach, from cherry, for Beads of Courage, and it was quite rewarding. I recommend an oil finish.