What happened

It's the afternoon of the week's final trading day -- and it looks like it's going to end on a down note for electric car stocks.

As of 1:25 p.m. ET, shares of industry pioneer Tesla (TSLA 12.06%) are edging down 2.6%, while upstart luxury electric car rival Lucid Group (LCID 1.19%) is suffering a much steeper fall, down 7.8%. Stuck in the middle is electric truck specialist Rivian Automotive (RIVN -2.21%) stock, suffering a 5% loss.

And yet, it looks like Rivian may be to blame for much of this mess.

So what

Sure, there are other theories for why the stock market as a whole is in a funk today. CNBC points out that many options contracts are due to expire today, warning that this carries a risk of "increased volatility" (and indeed, we're seeing that). Other pundits note that rumblings from the Fed regarding a continuation of interest rate hikes -- which make bonds relatively more attractive investments than stocks -- could be a drag on the market today. This, too, could be part of the story.

But if you ask me, the bigger, EV-specific news today is Rivian's announcement that it is canceling pre-orders of the least expensive (although at $67,500 per, hardly in-expensive) trim level of its R1T electric pickup truck. As MarketWatch reported late last night, the Rivian R1T "Explore" truck will no longer be sold, and anyone who pre-ordered the truck will need to choose between canceling their pre-order or converting it to a pre-order for an R1T "Adventure" truck -- for $73,000.

Rivian is also canceling pre-orders for its cheapest R1S electric SUV, which once cost as little as $70,000 and now can't be purchased for less than $78,000.

Now what

Rivian explained its action with a multiple choice answer: Either (1) it canceled because "only a small percentage of customers have chosen [the Explore] configuration," and the more expensive Adventure configuration is more popular; or (2) Rivian canceled the Explore to "streamline our operations, simplify our supply chain and ramp production."

Okay, maybe it was a little of both. But if you ask me, reason No. 1 doesn't make a whole lot of sense because, as a general rule, consumers like cheaper prices.

Reason No. 2, on the other hand, aligns better with Rivian's attempt back in March to push through a price hike on both the R1T and the R1S, citing "inflationary pressure, increasing component costs, and unprecedented supply chain shortages and delays for parts." Rivian had to back off that price increase in March due to customer outrage, but now it looks like Rivian has found an alternate route to raising prices -- declining to sell anything but the more expensive trims that can more easily absorb the inflationary cost of more expensive auto parts.

So...problem solved?

If Rivian is above-board about the unpopularity of its Explore package, perhaps. But if it's being disingenuous, then canceling its most affordable trucks could easily dent demand for Rivian's electric trucks, hurt its sales, and give rival electric vehicle sellers, such as Tesla and Lucid, the upper hand.

Then again, Rivian has to be aware of this, suggesting it may have had no choice but to de facto raise prices like this to combat rising inflationary pressures on electric car parts. And in that case, it would be reasonable to assume that Lucid and Tesla are facing this same dilemma -- potentially denting not only Rivian's sales going forward but also Lucid's and Tesla's. (And this assumption seems even more reasonable given that Tesla, at least, has already begun raising prices).

Indeed, when you consider the effect Rivian's bad news is having on shares at Lucid and Tesla, I'd say it's pretty clear this is what is worrying investors today.