More to the point, both point of views have utility. I criticize "my time has a numerical value" in the post, but it is useful to have some metric in order to get your fair market value (i.e. in negotiations) or when you are in a period where all you want is to gain monetary freedom.

In my original draft I had the mentioned reasons titled "the factual" and I started another section titled "the existential" [reasons I find the principle problematic], where I started to delve more into why perhaps you don't want to put a price tag at all. But as the post deals more with concrete criticism and possible improvements of the application of such a price tag and assuming its existence, it felt out of place and I decided to explore it more in another post.

EDIT: also, as another wrote here you do have situations/periods in life where you may need to apply such a metric and then proper application and self-reflection is important.

When the iPhone App Store had just launched years ago, I saw that all of the tip calculators focused on exact calculations, even making a point of excluding the state tax from the tip. At least one went so far as to incorporate a state tax rate database! My idea was to write a tip calculator app that put things in perspective, that rounded and swagged, with the intention of making tipping and payment easy while influencing people's perspective and generosity (e.g. Just put down a $20 bill rather than $19.42 or if you're paying CC, tip $4 in cash rather than $3.91 on your card). Then I realized that by having people use a tip calculator I was undermining my own message! Anyone who is uncomfortable with "Just take the bill, divide by 10, then double, and round. If you aren't poor, be generous" just doesn't get it.

What is the cost of living an anal, money-focused life? See my other comments.

eevilspock, who is obsessive about food, the anorexic saying "I don't need to focus on food" or the person saying "there are different ways of utilizing food, I should be thoughtful which is healthier for me and for my current goals"?

There's a case to be made that being the third person who says "All my life are defined by the exact amount of calories I'm eating" is unhealthy like the first one, but saying that these are the only kind of people who gain value by food advice is a stretch.

"Monetary freedom" makes limited sense to me - free from what? Free from having to be productive (to other humans in society) in order to get food and keep your shelter?

Free to take time off for travel or family when you want, rather than wait for set vacation days.

And so on. Most people have some things they'd rather be free from, if they had more money.

If you already have total monetary freedom, count yourself lucky.

You have to decide, what makes you happiest? If it is freeing up your time to do something else, then you might even pay a premium to have someone paint your house for you.

Until paying for stuff starts to mean you have to go to work more, thus cutting into your "free" time from the other direction. i.e. you're not spending your "free" time painting your house, you're spending it working to pay someone else to paint your house.

Exactly, ultimately these are all pathways to the same question/answer.

a. Good, please contribute to the discussion

b. Different reasons resonate with different people. Therefore someone's "core of the principal" isn't the other's.

As almost everyone here has pointed out, that's just NOT what the concept of "Times is Money" is about. BTW, the different reasons ARE the core of the principal. Of course people are going to make different decisions. But, I guess for you it only works when Billable hour > cost of item.

The first is that all valuable things can be measured in terms of other valuable things--including dollars. Opportunity cost tradeoffs of all types can be mapped onto a tradeoff for some quantity of dollars. All things can therefore be measured in dollars, even if you want to be silly and peg the value of things like "true love" as infinite--that's equivalent to infinity dollars. Your time is measurable in money as well.

The second point follows from something either you or someone else noted before. Eventually, paying for things that aren't worth your times adds up, and you have to work more yourself. That's the point! If you can earn more in an hour at work than you would have "earned" by spending an hour painting your house, you make money at no additional expense of time or effort. Alternatively, you could make the same amount of money as you would have gained in house/aesthetic value from painting the house, but spend less time doing it since you are more efficient at work: a time savings. Now, it isn't easy to just "work an extra hour" and get paid for it, but if you make these decisions constantly and trade more time at your job for paying other people to do stuff that isn't worth your time, you'll amass enough saved time to increase your work schedule by a reasonable block.

The key to understanding all of this is that you want to say that the concept of opportunity cost extends beyond money, which it does in a sense--but in another, since all things can be measured in terms of all other things, all opportunity costs have equivalent dollar costs. And so knowing your personal per-hour opportunity cost in dollars is a great way to get a basic quantitative idea of what things are worth your time. If spending an hour with your family is worth more than the $33.74 an hour equivalent that you make at work, it doesn't mean that spending time with your family can't be quantified in terms of dollars; it means that it's worth more than an extra $33.74 but is otherwise difficult to quantify.

And curiously, let's say you reduce your working hours down to 30 a week, the bare minimum you can have to live modestly but comfortably, and spend all the extra time with your family since you love them so much. But why not reduce the hours to 29 a week? Losing that $33.74 every week would put you below the threshold that everyone is happy at. That means that now, $33.74 is worth more than spending the extra hour with your family. In essence, this example shows that the fact that people go to work at all demonstrates how dollar values can outweigh "immeasurable" things like sentimental values, and since they can outweigh, they can be compared, which means that sentimental values have a relative value to marginal dollar value increases or decreases. Therefore, sentimental values can be translated to dollar values. This is a specific case of the general principle noted before, that all things can be measured in dollars, and so it's no sin (and in fact quite handy) to use your dollar/hour opportunity cost liberally when making decisions on how to spend your time.