Another issue that can occur is threads of carpet that roll up around the floor brush and restrict its movement, like the stuff on the bottom of the newspaper. Our vacuum won't pick up a penny, it just clatters away in the rollerbrush casing. Airsoft and regular beebees just roll away from the vacuum- it can't get them up, which is another good reason why they shouldn't be fired in the house!
Our local high end vacuum store once had a sign up "Break the junk vac habit". It also advertises "If you get tired of buying a new vacuum every year, come see us". I do go through vacuums quickly, and I don't vacuum very often! We have had many cheap vacuums and one expensive one, and they all seem to be about the same. Being able to trouble shoot a vacuum has been very useful knowledge that I somehow picked up along the way.
