Your footwear could be loosing it's strength because it's DWR pores are full of dirt and oil. The NIKWAX Fabric and Leather Proof is a great product and will prolong and revitalize any DWR finish. But you can't use that alone. You first have to clean the boot with the NIKWAX Footwear Cleaning Gel to get those pores cleaned out and help the DWR do it's job. Think of it like waxing a Mustang that is covered in dirt, it's not going to do anything but make more of a problem.
Comes in a Spray on and Sponge on Option!