Articles that hand wave it as “due to inflation” are a bit frustrating.
Recently (last six months) it has become clear that more raw prospects were opened than actual demand existed for (glut of future supply), as a result a number of 'fresh' lithium mines have been recently shuttered.
In the post mining concentrate processing game ground has been broken on several processing plants that take mined concentrates and produce usuable raw minerals - Tesla in Texas, for example, now has a pipelined spodumene processing plant and adjoining battery manufacturing facility that will soon be completed.
Much of this flux from expensive to cheaper comes about from the interplay of forward contracts - it takes 18 months and more to bring new mines to production, to bring processing plants to completion, etc.
What's behind the drastic downturn in nickel and lithium prices, and what does it mean?
https://www.abc.net.au/news/2024-01-26/examining-the-drastic...
Generally, there’s a lot of economics principles at play. Economies of scale mean as more is produced, often, still further increases in production are possible more cheaply than previously obtained. First semi chip produced might cost billions. The billionth chip might be pennies. There’s also a concept in the environmental economics that pulling finite resources out of the ground responds to increasing demand similar to pulling more money out of a bank via loans. Ie the most easy to obtain resources are mined first and the cost increases from there. In practice, too, producer relationships matter. A company buying batteries for EVs (ie at that scale) for their 5th year in a row is going to have demonstrated to their suppliers that, indeed, they can write a check for all the materials they’ve ordered much more than in year 0. So their suppliers have better information about how reliable their needs are, and so on.
Lots of complicated things not generally in the public knowledge nor easy to explain quick enough to not get scooped by another organization.
https://www.energy.gov/eere/vehicles/articles/fotw-1329-febr...
I've spent a fair amount of time looking for such a forecast that was actually more aggressive than the real popularity.
Your own link only shows a rather big increase in EV sales in the US, not a decrease, and it doesn't show any missed forecasts.
There was definitely a flurry of bad mass media articles about how the traditional car makers were scaling back their plans. But the facts in these articles were either extremely stilted and biased, or the facts in the articles directly contradicted the headlines.
For whatever reason, the car majors decided they wanted to tamp down on EVs in the media, and editors came through in spades with deceptive articles.