Chinese electric car company Li Auto (LI 6.69%) is ending a strong week on a weak note Friday. After reporting powerful Q4 earnings on Monday, Li shares climbed as much as 33% over last Friday's close. Today, the stock hit a bit of a speed bump, though, losing 3.5% through 10:30 a.m. ET after reporting its February delivery numbers.

But this was to be expected.

What Li Auto did in 2023

Li's performance in 2023 was simply fantastic. Sales surged 173.5% year over year to $17.4 billion. Gross profit margins expanded by 280 basis points to 22.2% -- twice the profit margin of General Motors or Ford. Free cash flow grew 19-fold to $6.2 billion. And net income flipped from a 2022 loss to a 2023 profit -- $1.7 billion.

At a market capitalization of $45 billion and change, Li Auto stock looked like a pretty obvious buy at 27 times trailing earnings -- but with a growth rate in the triple digits. And yet, Li ended its 2023 earnings report with a warning about 2024.

From one perspective, things would continue to go just fine for Li, with management anticipating 90%-plus sales growth in Q1 2024, as compared to Q1 2023. From another perspective, however, it seemed like Li was going to have to tap the brakes: Compared to the fantastic numbers that Li reported in Q4 2023, Q1 2024 would look a bit downbeat, with car deliveries falling at least 22% sequentially, and revenues falling about 24%.

What awaits Li Auto in 2024

Today's news confirms that warning -- and even suggests that things might be worse than Li thought earlier this week. Li has just announced that it delivered only 20,251 EVs in the month of February. This represented a 35% decline in deliveries from January 2024 -- worse than the decline predicted for all of Q1. It also represented only a 22% year-over-year increase against February 2023 -- not the 90% growth Li promised just a week ago.

So what does this mean for Li stock long term? Maybe nothing. The last thing we want to do is overreact to one single data point from one single month when investing for the long term. But we also don't want to ignore evidence that contradicts the reason we're investing in the first place.

For Li, this thesis is that the company is already making a lot of money and growing very strongly (even if not quite as strongly as last year). February's report suggests that Li's growth rush may be ending sooner and slowing faster than anticipated.

Caveat investor.