I have been using a Dyson vacuum for about 6 years now and have noticed a reduction in cross section over the last few months. In an attempt to restore original performance I replaced the Dyson cyclone assembly and what a difference! My vacuum cleaner is like new again. I suspect that dust accumulation inside the build over the years has started to affect performance. While I occasionally used canned air to clean the build, cleaning on the fly seemed to have less and less effect. Buying new is better than buying a brand new vacuum cleaner