The answer to 'why is my vacuum discolored' is that the discoloration is likely due to a buildup of dirt, dust, and debris inside the vacuum cleaner. Over time, these particles can accumulate and cause the plastic or metal parts of the vacuum to become discolored or stained.
Some common causes of vacuum discoloration include not regularly emptying the dust canister or bag, not cleaning the filters, and not properly maintaining the vacuum's interior components. The discoloration may also be caused by using the vacuum on carpets or floors that are heavily soiled.