I ve used waterpiks for about a decade. I have nev...

I ve used waterpiks for about a decade. I have never had one of these things last more than 2 years. The button that stops the flow of water always gets stuck after a year or so. This has happened in every single one of the waterpiks I ve had over the past 10 years, and I ve gone through 6 of these now. I don t understand how the design could be this poor.