OK, what the hell. I'll bite.
Anyone can parrot the texts without having any idea what it means, so I would expect you to explain your assertion in more detail.
when the demand rises and the supply doesn't, prices climb. this is because there is less of the product available per prospective customer, so they may have to pay more to assure their supply of the product.
inversely if the supply goes up and the demand doesn't I may have to sell it cheaper, due to the fact that prospective customers would have more options as to where they could get their product, so I may have to cut prices to compete. also when supply outpaces demand you have a slower turnover rate you begin to take on other costs (storage or maintenance of the product while you wait for a sale to name just 2).
so in a low demand situation these costs could actually make the sellers cost higher but their sale price lower making your theory complete horsetoejam.
as another example- say I manufacture pot holders (just crappy little cloth things to set hot pots from the stove on), and it costs me $100 per unit to make them. but nobody wants them. everybody is making good money but there is no demand for my product and I have a warehouse full of them. how much would you suppose I could get for this item? manufacture costs are up, income of the population up yet my prices would be low. so again...
I would not bother to explain now why in the long term the price of any product is determined by the income of the population and costs of manufacturing.
..is horsetoejam
however if there where only a couple units of my product available for sale and everybody needed one I could pretty much charge whatever I want (even if it cost me little or nothing to manufacture)
ok next point.....
So far I see you making the basic mistake of confusing demand with need.
ok this one is real simple. open MS word, type demand, highlight it, and hit 'THESAURUS'. this will give you a list of synonyms (words that mean the same thing.)
here I'll do it for you. here's the whole list...
necessity
claim
call
NEEDrequirement
charge
requisition
ultimatum