The cheapest flight that I could find goes from Milan to London and then from London to Hong Kong. Sure enough, it looks strange to leave from Milan towards North-West, whereas your final destination is in the South-East direction. The ever-changing fare policy of airlines can make this happen, though.
And when the flight takes off from London in the " wrong" direction (flights take off West-wards from the Heathrow airport), with 12 flight hours waiting for me, I utter "well, we're off to a fine start!".

I have never been on a flight for 12 consecutive hours. Granted, there is the excitement of the travel, the awareness that something unusual is beginning, that you are going to live an adventure and, more important, to know a new world, but 12 hours are, as a matter of fact, 12 hours. A vast selection of movies are available on board for sight on the display of the seat in front of you; you watch one of them, then again you look at your watch: still 10 hours to go. Ok, I mumble, let's be patient. I switch to reading - I brought the book The Poincare Conjecture by Donal O'Shea, which I already read to more than half, and I am resoluted to continue - after all, if I don't read while in vacation, when do I?

I read until I can stand it (the topic is not exactly a light one - in short it deals with the possible shapes of the Universe), but the clock, unforgivingly, reminds me that we are 9 hours away from destination. Most of the people are sleeping, but I cannot sleep on a flight[1].

These are the few times in your life when the time goes by slower than you'd expect: in the vast majority of cases the time flies too quickly. It never happened to me, as far as I can tell, that the time went by exactly at the right pace .
And when these circumstances happen, since they are very infrequent, you feel lost. You go to the toilet even if you don't need to, your thought wanders aimless, you think to problems that do not really exist, etc.

Eventually the hours go by somehow and, at last, we land in Hong Kong!

  1. ^In counterbalance, a friend of mine can sleep even on old buses which, without shock-absorbers, go on roads made from concrete slabs: when we were traveling together in the United States he arrived to destination well-rested, while I had rings under my eyes down to my chin.