By default a List displays a set number of records as specified in the system properties (accessible to System Administrators). For e.g if a Form has 2000 records and the list query has no filters (then all 2000 can possibly be displayed), however, the list setting is set to display only the first 1000 records then the remaining 1000 shall not be displayed (unless the user performs a search or filter to search for a value within those records, in which case they shall be displayed)

If no limit is to be specified then either the number of records should be set to a very high number or the list should be classified as a Paged View. 

Paged views display 25 records per page, however, all records are added to the list (although the List is paged)