The bottom seal for the motor compartment leaks and allows gunk to build up inside.
I love this device and had it for a little over a year when the motor stopped turning.  Being fairly handy taking and reassembling gadgets, I took it apart to inspect the motor.  When I took the bottom seal off the motor, it was full of "gunk" (no other way to describe it).  I cleaned the bottom seal and what I could inside the motor compartment (could not remove the motor).  Then I had to take the seal for the pump mechanism off and started to rotate the gear on the motor shaft (with the power off) to loosen the shaft (which appear to be jammed).  I turned the power on and continued to move the gear and shaft until the motor began to turn on its own.  I then blasted the motor compartment with WD40 and the motor spun flawlessly.  Left the device disassembled all day (to let it thoroughly dry out), reassembled and it worked like a champ.  Seems like a lot of trouble to save $35.00 but if I get another year out of it, the time spent was worth it.
Rating: 4 stars