[thatswrong0]

I guess it depends on what you mean by significant. It's true that, inherently, space flight is risky business.[0] This is new technology, so of course they are going to continue to uncover weaknesses even much further down the line once they start hitting a higher success rate.

But for the tiny bit of imperfect: the same could have been said for the space shuttle, and that had people in it. And its fragility was a fundamental to its design (it rode exposed on the fuel tank with its critically important heat-absorbing tiles). And the shuttle still had a decent success rate!

I would argue that these failures are less fundamental to the design of the rocket. And the difference is that if, in the future, you have that 1/100 failure on landing, it's only a loss from a cost perspective, not a human one.

[0] http://i.imgur.com/ei3h1B7.png