There have been a fair amount of launch failures over the yeares because as the old saying ("it aint rocket science, ya know") infers that launching large rockets is an extremely difficult thing to do WITHOUT a failure, even here in the 21st Century. It is so difficult, there really should be MORE failures. Essentially the rocket engines are great big BOMBS and we ignite them, and we have to prevent the huge bomb from blowing up the payload. That aint easy. In fact, it is beyond the most difficult thing to do. There are other factors that make rocket launches very dicey, such as winds aloft, and more. That's why so many Shuttle launches were delayed or "scrubbed" not to mention several such delays to launch of communications satellites because conditions have to be JUST SO nearly perfect for a successful launch. This is why NASA and the private sector believe rocket technology just can't do the job of getting people into space for the future, both because of cost and how utterly a roll of the dice a rocket launch is. The problem is that it is still "rocket science" and not "a walk in the park," which has it own dangers
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