Just the opposite. The database should always provide default values that ensure that records added are valid and meaningful. Remember, you cannot predict at the time you write the application what code will eventually be adding records to the database.
That's not to say that you may not have a second level of default data specified by the application that depends on the application state at the time the data is created.
So, imagine that you have an employee status code that can be "P" (propect), "A" (active), "T" (terminated), or "R" (retired). You should specify at the database level whether people enter the system as "P" or "A", for instance (or perhaps a fifth code for Unassigned). But your application can and should require the user creating the employee record to select one of the options from (for instance) a group of radio buttons and use that value when INSERTing the record.
