I ran 3.5 kms yesterday. I just needed to do that 11 more times and I'd have ran a marathon. Easy-peasy.
900m to the next aid station is not "almost a km", it's only "a little more than half a mile".
Ran 14 kms? That's not, "only 1/3 of the way". It's, "Ok, just do that two more times".
It's not, "10 kms left". It's, "Just a Sun Run left".