On airplanes, there is a so-called 'inertial guidance system', the purpose of which is to get the plane within a thousand yards of the runway right before the estimated arrival time.
Each time the plane strays off course, the system corrects it.
Planes would therefore arrive on time and on course despite 'having been in error 90% of the time'.
So the path from here to where we want to be starts with an error, which we correct, which becomes the next error, which we correct and that becomes the next error, which we correct.
So the only time we're truly 'on course' is that moment in the zigzag when we actually cross the true path.
The trick in life is not to worry about making a wrong decision; it's learning when to correct it.
(from Susan Jeffers: Feel the fear and do it anyway)