The speed and convenience of Amazon’s own delivery network has regularly come at the price of safety, as detailed today in an extensive report by BuzzFeed News and ProPublica — including the death of Joy Covey, Amazon’s first CFO, who died when a van delivering Amazon packages turned left in front of her while she was riding her bike.

As Christmas approaches, Amazon deliveries are being raced across the country to get to people’s homes in time, and over the past few years, more Amazon-branded vans delivered those gifts — rather than the United Parcel Service or United States Postal Service. That’s because Amazon has made a concentrated effort to grow its own delivery network, allowing the company to control its own logistics and deliver more packages faster, and the company now delivers more than half of its own packages.

The report details many ways Amazon has sacrificed speed for safety to grow its delivery network and how drivers have made dangerous decisions to keep up with the demands of their job. For example:

In the lead up to last year’s holiday season, Amazon said it would make a five-day course to assess and train new delivery drivers to help improve safety. That class was never implemented, and an Amazon memo said that the company “chose to not have onroad practical training because it was a bottleneck.”

In 2013, early on into Amazon’s work building its own delivery network, a proposal to improve driver safety by giving longer rest breaks — and capping packages per route. That would have added an estimated cost of four cents per package, if it were implemented. But it was apparently shot down by Amazon exec Dave Clark, who is currently the company’s SVP of Operations. He called the proposal “garbage.”

Drivers rely on an app called “Rabbit” to tell them which packages to deliver and where to deliver them. An early version of this app apparently gave very poor directions, navigating drivers onto dangerous routes, and some drivers felt they were under such time pressure for deliveries that they didn’t take breaks for meals and would urinate into bottles. Amazon told BuzzFeed and ProPublica that it has made more than 500 changes to the app this year.

Those are just a few examples, but I highly recommend reading the report in full.