Despite Amazon spending almost a decade and $2B+ developing drone delivery services, sources say it's still beset by technical challenges, safety concerns, more (Bloomberg)

Bloomberg:
Despite Amazon spending almost a decade and $2B+ developing drone delivery services, sources say it's still beset by technical challenges, safety concerns, more  —  Jeff Bezos went on 60 Minutes in 2013 and pledged to fill the skies with a fleet of delivery drones that could zip parcels to customers' homes in 30 minutes.