Node lássuk mit ír a NASA a Falcon 9 megbízhatóságáról:

Reliability This flight represents the 17th flight of the Falcon 9, following 16 successful missions. An analysis of launch failure history between 1980 and 1999 by the Aerospace Corporation showed that 91% of known failures can be attributed to three causes: engine failure, stage-separation failure, and, to a much lesser degree, avionics failure. Because Falcon has nine Merlin engines clustered together to power the first stage, the vehicle is capable of sustaining certain engine failures and still completing its mission. This is an improved version of the architecture employed by the Saturn I and Saturn V rockets of the Apollo program, which had flawless flight records despite the loss of engines on a number of missions. With only two stages, Falcon 9 limits problems associated with separation events. SpaceX maximizes design and in-house production of much of Falcon 9’s avionics, helping ensure compatibility among the rocket engines, propellant tanks, and electronics. In addition, SpaceX has a complete hardware simulator of the avionics in its Hawthorne factory. This simulator, utilizing electronics identical to those on the rocket, allows SpaceX to check nominal and off-nominal flight sequences and validate the data that will be used to guide the rocket. SpaceX uses a hold-before-release system—a capability required by commercial airplanes, but not implemented on many launch vehicles. After the first-stage engines ignite, Falcon 9 is held down and not released for flight until all propulsion and vehicle systems are confirmed to be operating normally. An automatic safe shutdown occurs and propellant is unloaded if any issues are detected.

https://www.nasa.gov/sites/default/files/files/SpaceX_NASA_CRS-6_PressKit-2.pdf

Tehát a SpaceXnek van egy olyan hardverszimulátora amilyen a többieknek nincs és ezzel máris értelmet nyert miért nem végezték el az ULA-ban az e2e tesztet, illetve miért tart ott napokig egy ilyen teszt összeállítása.