What does the ECO TUB CLEAN indicator mean?

The ECO TUB CLEAN indicator reminds you to clean the tub when necessary. If the indicator blinks after washing is complete, remove the laundry and run the ECO TUB CLEAN cycle. The reminder remains active for 6 consecutive cycles immediately after each cycle is complete, though you can ignore it and continue running cycles normally as this is not a system failure. (Page 38)