The law of increasing marginal cost does not fit the reality.
law of increasing marginal cost : When you make a lot, the production cost goes up.
This is the opposite of [economies of scale
Even as a practical matter, marginal cost goes down with mass production.
So I looked it up and found some discussion about it.
The upward-sloping supply curve focuses only on the mass-production part of the U-shaped average cost curve shown below.
https://gyazo.com/7dd35c64ac7e9b7d61c6354bfd1edd1e
The average cost curve is the slope of the line connecting each point of the total cost curve to the origin.
As for new manufacturing from 0 to 1, the supply curve is falling right
https://gyazo.com/8541f44cfa945c9b9b80589f577b4cd9
If the supply curve exceeds the demand curve, the supplier "is in the red" and the demander "is too expensive".
If this is reversed, the supplier "is in the black" and the demander "wants it!" and the demander says, "I want it!
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