[Animats]

If you're able to get a 50-story stack into orbit, the rest of the trip is not that difficult.

[adolph]

https://en.wikipedia.org/wiki/List_of_missions_to_the_Moon

This records 165 attempts including non-crewed missions of all types, like flyby of impactor. Of 165, 87 had some form of failure. 40 at launch, 32 at spacecraft and 5 partial failures. 32/(165 - 40) is .25, so about 3/4 of the time a moon mission launched, it succeeded. This indicates to me that "the rest of the trip is not that difficult" mischaracterizes the difficulty.

  > $x("//tr/td[7]").length
  165
  > $x("//*[contains(normalize-space(text()), 'failure')]").length
  87
  > $x("//*[normalize-space(text()) = 'Partial failure']").length
  5
  > $x("//*[normalize-space(text()) = 'Launch failure']").length
  40
  > $x("//*[normalize-space(text()) = 'Spacecraft failure']").length
  32