I empty mine at least once a week. I have a son with long hair, a cat that sheds like i dont even know what, plus the pollen and dust from daily life. I just take my shopvac and vacuum it out, clean the filter, and empty the little canister thing attached to the vacuum, not the base.
Otherwise, mine came with 2 brand new extra bags and 2 new sets of mop pads. I assumed both needed to be replaced
I guess you could say I'm OCD. I clean my X50 Ultra every time it's used. I empty the bag, turn it inside out, and with an air compressor I blow it out. I then turn the bag right side out and blow it out again.