[Aurornis]

This is just semantics. If it becomes untenable to supply a good at a given price, the supply for that good decreases.

Then supply and demand reach equilibrium.

Supply and demand doesn’t mean that either or both supply and demand remain constant. Both supply and demand change depending on the price.

[ceejayoz]

> Both supply and demand change depending on the price.

But that's a massive oversimplification. It's like saying programming is "just typing". Technically, sure; accurate, no. There's latency in the real world. Bad actors. Information asymmetries. Regulations. Monopolies. Stuff you can't do without and can't even always decline (ambulance ride for an unconscious person). Fake news about a supply crunch changes demand without changing supply for a while.

[ethbr1]

Most relevant in modern global economies: lack of available alternatives.

One of the primary reasons for combination in low-margin markets is to gain pricing power. And even if there are 2-5 entities in a given market, informal price collusion is far from unheard of.

If OP wants an intro to the determinants of price elasticity, starting here would be a good idea: https://en.m.wikipedia.org/wiki/Price_elasticity_of_demand