It is a hydraulic connection which is subject to leaking around seals. As was the fear when hydraulic brakes and power assisted steering were first introduced.
The fear with hydraulic brakes had little to do with the number of failure popints. It had to do with one point failing and taking the entire system down. With mechanicals one could fail and the other three would likely operate.
However, as we all know hydraulic brakes have been quite reliable for many decades now. As I'm sure we will find with electronically controlled throttles, brakes and steering.
Nothing is failproof - that is correct.