Does getting home from a trip seem to take less time than getting there? There's a scientific explanation for that!
NPR's Morning Edition explains the psychological phenomenon called the "return trip effect":
Here's what van de Ven thinks is going on: "Often we see that people are too optimistic when they start to travel," he says. So when they finish the outbound trip, they feel like it took longer than they expected. That feeling of pessimism carries over to when they're ready to return home. "So you start the return journey, and you think, 'Wow, this is going to take a long time.'"
But just as initial optimism made the trip out feel longer than expected, this pessimism starting back makes the trip home feel shorter.
http://www.npr.org/2011/09/05/140159009/why-the-trip-home-seems-to-go-by-faster
If you are helping someone move, the first half of the day seems like eternity, but 2nd goes much quicker. And of course, when traveling, the trip down always seems longer than the trip back.
My own guess is, when traveling, you have more anticipation on the trip out, which makes your brain constantly conscious of the time. On the return trip, your brain is more relaxed and less anxious, so you forget about the time.
On the way back, assuming you take the same route, you already have those markers in your head so you don't waste time searching for them but you do make a mental note that "yeah, I passed that before".
I don't think optimism or pessimism has a thing to do with it.
Reverse that and I'll buy it. An optimistic attitude lends to not being bothered so much which, to me, lends to making a trip feel shorter. It's that pessimistic feeling of having to drive... all...that...way...back that makes those car rides home seem so much longer. Usually, you're more tired and just want to be home. That's when it feels like forever.