"Once you get inside four minutes and you're headed to T-0, if
you have a problem you don't have time to discuss it. With a
one-second window there was no opportunity to try to resolve
this."
Source: NASA Spokesman George Diller, after the
launch of the Gravity Probe B experiment was scrubbed Monday. No
one was sure if they had loaded high altitude wind information into
the rocket's computer. Since time was of the essence, NASA decided
to err on the side of caution and try again Tuesday afternoon.