1) Really good ACS(ystems).

2) Really good real-time processing and commanding software.

3) Really good thruster function.

One of those things wasn't really good enough. But hey, sometimes it's even cheaper to just test by flying rather than perform several quadrillion analyses. Especially if human lives aren't on the line.

They will have arranged for real-time telemetry data streams from the rocket, so they'll know exactly what it was thinking up until the moment of its tragic suicide.

Ideally, you would see it float into frame more slowly and descend not unlike this.

And I also find this really damn commendable. The technology has to be developed. Is it a better alternative to docking verrrrrry slowly with a pod flange like we're doing for the ISS? I don't know... but it's certainly more badass. This is how we're gonna pull up to space fuel stations. In self-driving rockets. Then we step out of our vessels to grab a fuel hose, and what are we wearing? Fuck! We're wearing spacesuits!! Not clunky, fat-suit 1960's crap, but streamlined spandex sex (we're all in really good shape, too, because... it's the future, of course).