As data volumes grow, it takes longer and longer to load the data if you doing a full load every time. Eventually, it may take so long to do a full load that users can be blocked from using the data. This is remedied by setting large tables to be incrementally loaded. Incremental loading is a technique used to only load new or modified records into a table instead of re-loading the entire table (Full Load), therefore, drastically reducing the amount of time it takes to load these table.
This video will illustrate how Source Based Incremental Load can be configured in TX DWA.