It's not the case that they could guarantee 22 flights for the same cost, time, and mass budget. We only know that this design worked after the fact, they didn'

It's not the case that they could guarantee 22 flights for the same cost, time, and mass budget. We only know that this design worked after the fact, they didn't have that information in advance. Also, this design may only have achieved 22 flights by pure luck; maybe radiation hasn't struck a key microchip yet, or maybe the dust hasn't degraded the rotor motors as much as expected because there hasn't been as much dust as expected.