When I was at college, there were buses that ran on about a fifteen minute schedule to carry students around campus - Campus Shuttles. Two of the routes went between the dorms and the union building. I sometimes rode on those routes. I usually wasn't in much of a hurry, so I would just take whichever showed up first, even if the one coming a couple minutes later would get me to my destination sooner.

One day when I had some free time, I got on one of those buses and rode through the entire route, just because I wanted to. I did the same thing on the other route not too long after.