When the shuttle first flew--even up to when Challenger was lost--NASA were claiming about a 1 in 10,000 chance of losing a Space Shuttle. In reality, based on what we now know, the odds of losing Columbia on its first flight were probably about 1 in 10. With hindsight, the Space Shuttle was probably the most dangerous manned spacecraft ever built. The earlier capsules probably had a higher chance of a launch failure, but they all had escape systems. The Shuttle was going to be so safe that there was no need for a launch escape system. So much for that.
Originally Posted By: billt460
When the Shuttle Program was brought on line, NASA said that a total loss of payload, vehicle, and crew every 50 missions, was more than an acceptable rate of failure.
Falcon-9 has about a 96% success rate, which is quite typical for a new launcher in its first few dozen flights. As I mentioned above, now SpaceX can recover the first stages, they can see where there are problems in the design that might cause launch failures, and fix them.
Space-X is still very much in it's early stages. And they've had quite a few major failures already.