The majority of increasing demand is for products that already exist.
how could Demand "now" increase (or decrease) for "now-not-yet-existing" products ? Demand for "future products" resembles Investment.
I am not sure what your asking the question about. My point is that increasing demand is more on current products that currently exists, not on non-existing products.
I should define a couple of things. Demand is the actual purchasing of the product. Excess demand is demand that has not been satisfied by the ability to purchase the product because there is a shortage of supply.
Demand doesn't cause an increase or even the investment in future products. Potential demand may may if, like an I-pod, it has been advertised ahead of introduction to manufacturing, in which case it is the potential demand that causes production.
I am not getting how "demand for "future products" resembles investments", exactly. Investment can come in a couple of forms.
One is like venture capitalists that typically invest in a company that already has demand, can't keep up, and needs the leverage to tap the excess demand.
Another can be on a new product in which case it can be based on a "guess" that the product will sell or a marketing survey. A marketing survey might ask, "If this product was available, would you buy it?"
Instantaneous demand, or demand in any particular day, is not a constant or static thing. Technically, demand is the actual purchase of product. When there is excess demand, it triggers more production. Excess demand, of course, is not necessarily directly measurable or observable, except when there is something like a sale on a product and they have to give out rain checks.
Rather, vendors gauge excess demand by watching existing sales. When existing sales climb faster then expected, that is they run out of stock earlier then expected, it gives them the information they need to increase stock by increasing production.
Consider the guy that owns a cigarette shop down the street. If he runs out of Marlboros early, and customers keep asking for them, then he knows, he actually can measure excess demand. Each person asking for Marlboros that he does not have is excess demand. This prompts him to increase his order. This triggers the sales rep to tell production that they need to increase output.
Now consider the major grocery store chain. They don't have much interaction with customers that cannot find product, yet they seem to keep just a little more then they can sell, never really running out or over stocking excessively. The Hostess guy actually stocks the shelf himself, never interacting with customers. Instead, he count how much bread he has left over, and if it is only a couple of loafs, he stocks more the next day. He gauges the variability, keeping stock at the point that just manages to keep the shelf from running out.
For that matter, depending on the product, he might let it run out. This, though, wouldn't be a good idea as he wouldn't then be able to gauge changing demand.
Isn't that what happens?
I am sure you can think of all manner of companies and examples of how they gauge changing demand.
Oh, by the way, I didn't get back to it, but on that (M+C)V=PQ thing where C can cause an increase in prices. I forgot t, myself, that increases are to P or Q, depending of if output is near maximum or not. I know better but didn't make this obvious connection when thinking about C. My bad.
Since the recession, the demand for imports has fallen to 50% of what it was. Walmart, Target, and every manner of store has less demand then they did. The problem is, the excess demand doesn't exist. At first, when the recession occurred, demand collapsed on the collapse of consumer revolving credit.
Some of the recovery has been on an increase in the use of credit. In this case, the increased use of credit triggers increased output. (and some of it in China, which is pissing some people off.)