SpaceX Glitches - Countering Over-Engineering

Over-engineering? (Portland, OR)

SpaceX is arguably the most successful private/commercial/new space company to date. After being the third country entity to develop the technology and hardware that can bring cargo to the International Space Station and back, it's taking strides towards bringing people to the coveted destination in the sky, working on a version 1.12.0 of the Falcon 9 rocket and also on a reusable rocket, the Grasshopper.

With all the success SpaceX is having, we should not forget the problems and misses of recent launches, for example an shut-down in-flight and problems with thrusters required to get the Dragon to the ISS when in orbit.
From the SpaceX Updates page:

After Dragon achieved orbit, the spacecraft experienced an issue with a propellant valve. One thruster pod is running. We are trying to bring up the remaining three. 

One may look at these issues and be concerned about SpaceX design, manufacturing quality, engineering, redundancy and what not. I am actually encouraged by these glitches.