For me it should be intuitive. My test is "Will I accept either outcome if I flip a coin?". Is so, flip the coin. If not, pick the option that prevents me from flipping a coin.
If you have no way of knowing which choice is better then you would flip the coin of course. The problem is there typically is a way to possibly learn more about which is better, AND HOW MUCH, by studying the choices. The "How much" -part is crucial. One choice might lead to core meltdown.
Often such study does not provide any further information about which is better. But it might. You just don't know. Except if you are lucky and the answer is immediately obvious.
So if it looks like you have two choices A and B, it is more typically the case that you in fact have THREE choices:
1. Choose A
2. Choose B
3. Spend more time studying which is better, and how much, A or B
You spend a fixed amount of time, if no choice could be made during this period, then flip the coin.
The fixed amount of time could be as short as five seconds. Or the amount that makes sense to you, and you feel comfortable with. If it's one week for you, then it is.
If the choice doesn't matter much, then both options are equally good.
E.g. "should I get this pair of shoes or that? I like both".
Just get one and get on with it.
"Should I go to Paris or Vienna for a short trip?"
Just pick one and get on with it.
Still people obsess for these kind of choices for needlessly long...
The case discussed, were people waste time they shouldn't, is (a) when the choice doesn't matter much or (b) when you do know that either option would be more or less fine (which is basically a variant of (a)).
If (c) you can't tell if they're equally good AND chosing the right one does have a BIG impact, then this case doesn't fall under the advice of TFA or what we discuss here.
Rather, it's an "ipportant choice" and people should think it over...
Based on my own experience as a SW developer I have found that more often it is hard to know beforehand whether a design-choice matters much or not, and how much.
I suppose that is also the reason for much of "Technical Debt". People make less than optimal design choices not because they are bad designers, but because trying to evaluate the benefits of each choice would be too time-consuming.
It's of course possible to be wrong in either direction -- this difference matters though i think it doesn't and vice versa -- but in general, we tend to be pretty good about taking seriously the things that really are serious, but pretty bad at not wasting time on things that don't matter much. This shows up in the paradox of choice, but really just imagine someone hemming and hawing over two brands of cereal in the aisle at Trader Joe's and you get the picture.
So the practical problem isn't really "how do you know until you analyze," because we more often fall into opposite the trap and waste time systematically attempting to optimize choices where there is little value to be gained. We should step back in more cases and remind ourselves that most differences make no difference at all. Save your time and energy for the ones that do.
Big decisions are often like icebergs. Most of the important stuff is hidden below the surface. No matter how much you analyze the tip you still have an essentially 50% chance of getting the decision wrong. It's really hard to make a major decision knowing that you have a 50% chance of getting the decision wrong, but over-analyzing the tip of the iceberg is not going to improve your decision making.
There are a lot of insightful heuristics from decision making that can make big decisions much better/easier/etc.
I don't think people would spend any more time on big decisions if they made faster/fewer decisions with little "value" to gain, if anything I think their habit of making fast decisions would mean they spend less time/worse on the big ones!
And no doubt that sometimes it's just nice and pleasurable and interesting to deliberate over anything at all, making small things grand, but it's also good to know when it's actually optional.