The rings are elevation placements. Less would be "correct in that they’d still signify elevations, it’s just less detailed.
For example, the widest ring might be an elevation of 2470ft while the smallest ring might be 2570ft. If there are no rings in between, it’s still correct, you’re just not getting very detailed. You could easily be looking at a perfect sloap on all sides, like a smooth cone. But place 9 rings in between at 10ft more of elevation each, you’ve got a much more detailed idea of how a mountain or hill is shaped.
The rings are elevation placements. Less would be "correct in that they’d still signify elevations, it’s just less detailed.
For example, the widest ring might be an elevation of 2470ft while the smallest ring might be 2570ft. If there are no rings in between, it’s still correct, you’re just not getting very detailed. You could easily be looking at a perfect sloap on all sides, like a smooth cone. But place 9 rings in between at 10ft more of elevation each, you’ve got a much more detailed idea of how a mountain or hill is shaped.
So, correct, but not very useful.
Utility may be subjective, but sloap perfection is forever.