Why can't you fly up Everest?

Could you elaborate on why it's not feasible to fly up Mount Everest? Are there any specific challenges related to the mountain's altitude, weather conditions, or terrain that make air travel impractical? Is there a technological limitation currently preventing us from achieving this feat? Or is it simply due to the fact that the mountain's summit is not accessible by conventional aircraft? I'm genuinely curious to understand the reasoning behind why flying up Everest isn't possible.