This happened to me last week. So I was at my university waiting for the bus. Now there are two buses I can take, let's just call them Bus A and Bus B.
Let's assume the number line is the path of the bus and the university is at $x = 0$ (and $x\geq0$).
My destination is $x = 2$ and Bus A takes me straight to there. Bus A on the other hand only takes me to $x = 1$ and to get to $x = 2$, I have to wait at $x = 1$ until a Bus B comes and takes me to $x = 2$.
Assume that the traffic level is the same and both buses have the same speed/acceleration.
What happened me to last week was that I waited for Bus B to come, but it didn't so I decided to take Bus A which took me to $x = 1$ and as soon as I got out of Bus A, I see a Bus B speeding up from behind and I got onto Bus B immediately.
How could this have had happened?