Consider an Order form with Product Name and Quantity fields. The default value for Quantity field can be set as "1". When the form loads, the Quantity field value will be preset with the value "1". This value can be edited by the user while accessing the form.
Similarly, you can set the field value in various scenarios such as displaying the default credit limit of an account in a CRM system, setting the default value for a device request in an IT asset management application and more.