Yeah; continual miniscule course corrections. I use the analogy
  of trying to hit the moon. Even landing on that asteroid wasn't
  "let's calculate perfectly then launch and forget about it".
  Trying to get everything 'right' is an ongoing process that's
  involves a few big course corrections and a whole lot of little
  ones. Even the slightest error and you miss the target entirely.
  so even a miniscule course correction, in that context, isn't so
  miniscule at all. A percentage of a degree off at one point, and
  you can end up in nowhere-land, as it were, before you realize
  it. Still, I couldn't be INTJ or related types... it seems to be
  a painful place to be, with everything logical and clear and the
  world seeming full of ridiculousness and few who seem to
  comprehend. You tweak, try to help, and you get an emotional
  outburst in return for your assistance. At least, that's my
  impression of INTJ and perhaps INTP as well... but I dunno - I'm
  not an expert at these things... just observations.