Sometimes, on race day, the stars, moons and planets (and any extra powers that be) will all align.
And, sometimes they don't.
The weather may be undesirable. The course may be unexpectedly tough. Your body may feel fatigued or your energy level is in the negative. Or, all of these factors could show up at the start line, give your mojo a run for its money, and wreak havoc on your race.
Such was the case for me on my most recent race day.