Because vinyl and linoleum flooring is so soft, if someone wears stilettos on it, it can dent the surface, particularly when the room is heated. And because the ringed dents are usually ringed with black, they are quite noticeable on light colored flooring.
If your lino is dented, there is one thing you can do to try and fix the flooring. You need a hair dryer and plenty of patience. Simply wave the hair dryer over the spot and about a foot wide area around it. You want to not just heat the specific one inch spot, but the area around it.
When the flooring is heated, sometimes the floor becomes pliant enough that the rings will “release” from the fooring and go back to its original flat shape.
If this does not work – and it won’t work on all floors – the floor will need to be replaced or you can use small strategically placed mats or carpets to try and hide the dents. A good scrubbing with bleach can help remove the ringed black marks from the floor to make it less noticeable.