All saved solutions are listed along with their descriptions. Buttons in the window control the management of your saved solutions. Deleting unwanted solutions this way deletes their name from this list as well. For large models with large solution workbooks, rounding greatly reduces the storage size of the workbook.
Rounded numbers are sometimes neater for presentation purposes as well.
You should make it a habit to manage your solutions from this window. Although you can manually delete solutions in Excel, doing so from this window updates and keeps track of your solutions in an orderly way.