It's absurdly easy to go from 1st to 10th within a second, a tiny bit before the finish line.
Granted, it's also possible to go from 8th to 1st within a second, turning a solid 8th through the entire track to a "WTF? I made first!?".
And given that I kinda need first on all four tracks to even make a star rank (required for unlocking some things), it's pretty frustrating when my 1st place vanishes moments before the finish line, because of some retarded flying blue shell of doom. Or someone behind me grabbing a mushroom or a star. Or even the flying bullet of awesomeness, which I've used myself to score a 1st from a 12th.
But yeah, I've still got 9 characters to unlock and goodness knows how many karts and bikes. Also haven't unlocked mirror mode either. :P