I like to say Bissells are sneaky. Even with routine maintenence, they will have a shortened lifespan compared to what how long the motor could last. For example, even if you never cleaned your pre motor filters, no dirt(at least visible, or up to say 95%)should get past the filters. However, I have seen one too many near new/broken in Bissells that had hepas and the motor cases covered in dirt, pet hair and such even with the filters properly installed and once even with them cleaned regularly. The hepa filters do the dirty work for Bissell and the like; you think your vacuum is working perfectly because it's not spewing dust out or making noises(yet) but every time you use it the motor sucks in more dust. So maybe they need to revise their filtration system, or put in stronger pre-motor filters. Either way, this has been going on for years, and I'm sure everyon in manufacturing at Bissell is aware of what's going on in their machines, but they don't give a darn because sales of their junk are good.