My previous Keurig coffee maker lasted for 9 years! 
I believe these Keurig Water Filter Cartridges had a lot to do with it’s longevity.
When your Keurig coffee machine tells you it’s time to change the filter, do so!
Proper care & maintenance only takes a minute or two and is important if you
want to enjoy your Keurig coffee machine for a long & enjoyable time, especially
If you have hard water in your area.  Even if you do not have hard water, you will 
be able to enjoy the taste, aroma & pleasure that a clean, well maintained Keurig
coffee machine will produce.