You can afford to undercut profitable companies when you set OPM on fire.

You get what you pay for: with ULA, your payload makes it to orbit/space every time. With SpaceX, there's a significant non-zero risk of losing your payload, and that risk discount is what lets SpaceX undercut ULA. (That risk discount is also why SpaceX has to severely undercut ULA; the economics from a customer perspective wouldn't work out if SpaceX were only a small discount from ULA prices.)

Are you talking about Zuma?

There's "no explanation" because it was a classified launch, and the indications we do have are that it was an issue with a Northrop Grumman payload adapter.

ULA's perfect score is a bit of a cheat, as the rockets they launch were inherited. The first flight of the Delta IV Heavy, for example, was a partial failure... but happened before ULA's formation.