What was the goal here, exactly?

Idiots and fire don’t mix, but it sure is fun to watch! Give a real dumbass a big enough explosive, and you’re bound to witness either something hilarious or an injury so deeply traumatizing that it will put you into therapy for years.

Thankfully, this is the former. These dudes somehow tried to make a shop vac flamethrower. Unfortunately for their lawn and skin, they succeeded.