Shoddy components.
It's a fire. You turn it on and it warms the air. HOWEVER the manufacturers have deliberately made sure the one component that receives 90% of the wear, viz; the rotary switch; is designed to fail catastrophically after 1 year and a few days. IE built in obsolescence like jap cars of the 70s.
No need for lazy design and atrocious workmanship, but they still do it.
Verified purchase: YesCondition: New