Don’t map variables is the default behavior.
When variables are not mapped, there is no transfer of data between process variables and other models within the process.
For example, if Don’t map variables is selected for a user task in a process then none of the form fields will be populated with values from earlier within the process instance. Similarly, when the form is completed none of the values entered by the user can be reused later in the process, such as within a decision table.