Opportunity cost is exactly as your quote says
"Assuming the best choice is made, it is the 'cost' incurred by not enjoying the benefit that would be had by taking the second best choice available."
You have choices A and B. A seems to be the best choice, so you go with it. The opportunity cost is B. You sacrificed it for A.
Both choices were good choices, but you sacrificed the good of one for the better of the other.
So the opportunity cost is basically the thing that you did NOT get, but has similar value/features to the thing that you got. Because the thing that you got is better than what you did not get, which is the opportunity cost. Am I getting this right?
Not exactly. Opportunity cost is the loss of some potential income due to a missed opporunity, to put it simply. Normally in a situation where you have two choices (A or B), and you pick A, you might consider the income you would have gained from B to be the opportunity cost of picking B. Normally you wouldn't bother, because any loss would presumably be offset by the option you did pick - which is presumably better - but it all depends on the situation.
Another example of opportunity cost would be the piracy claims film and game companies make. They say that thousands of people torrented their game instead of buying it. This means they have incurred an opportunity cost, because the torrenting of the game means they have lost the
potential income they would have gained from that person buying it. Obviously with regards to piracy it's a fallacious argument (not everyone who pirates the game would have bought it otherwise), but applied to other situations it's a more useful accounting concept. But only ever an accounting concept.
So is it hard to actually get around in Tokyo at night? Do people there seriously enjoy walking a lot? Is there transportation around at night in Tokyo and in other cities? We're talking from 10 PM to 6 AM in the morning.
Compared to America there's probably a lot of walking. But anywhere has a lot of walking compared to America, since you guys go by car all the time.
The last trains are around 00:00 - 00:30ish, so how late you need to leave by to make it depends on where you're going. If you miss it, you might be able to get somewhere close-ish and then walk for a couple of hours, or failing that there are loads of all-night manga cafes etc which you can sleep in until the first train (at around 5am, I think). Or you can always get a taxi if you're feeling rich (but if it's too far to walk in a reasonable amount of time, that could get expensive).
There were actually plans to make train services 24/7 not too long ago, but they were dropped after it turned out that the majority of people actually didn't want 24-hour trains. It turns out a
lot of people use the last train as an excuse to leave company drinking parties etc early, and are worried about losing that excuse because they'd have no way to avoid having to stay out drinking all night
