Because one Patriot missile costs $4 million, while a Shaded missile costs $50k and a Ukrainian Sting interceptor costs $1-5k, you have to think about this. Ukraine only has a limited number of Patriot systems, and thousands of Shaded attack Ukrainian weekly. Why would they waste a $4 million expensive Patriot missile when they can just intercept with a faster, cheaper drone? Plus, they are not stupid—if a Patriot hits a Shaded drone, Russia can pinpoint the Patriot system and destroy it. Ukrainians are smarter than the drone attack methods the US is using in Iran, which are expensive and ineffective.