Tesla (TSLA -4.97%) stock had a rough first day of the 2023 trading calendar year, falling 12.2%. But shares were down as much as 15% at one point during the session.

The sell-off was largely due to Tesla's disappointing delivery numbers for Q4 2022, which were released on Monday when markets were closed. Tesla achieved record deliveries of 1.314 million vehicles in 2022, including 405,278 deliveries in Q4 alone. But many analysts, such as Wedbush Securities' Dan Ives, were expecting a Q4 delivery figure in the range of 415,000 to 420,000.

Tesla produced 8.5% more vehicles than it delivered for the quarter. It remains to be seen if the gap between production and deliveries was due to decreasing demand or logistics issues. Either way, the lower-than-expected delivery number adds yet another cause for concern to a stock that is down a staggering 59% in the last three months.

With the stock hitting a two-year intraday low on Monday, is now the time to go all-in? Or could there be more pain ahead for the electric vehicle (EV) industry leader?

A red Tesla Model Y parked in a lot with a mountain range in the background.

Image source: Tesla.

A tale of two investment theses

Daniel Foelber: As tempting as it may be to buy Tesla amid the steep sell-off, I think investors should first take a step back and decide what they believe Tesla's value proposition really is.

There are many facets to Tesla's business. The core is the production and sale of electric cars to consumers, which has a lot of room for growth in its own right.

But the bigger growth story is arguably the company's penetration into the trucking industry, as well as its proprietary autonomous driving technology.

There are plenty of companies that are working on lowering emissions for Class 8 trucks by substituting diesel for compressed natural gas or using alternative fuels. But no company has achieved the milestones that Tesla has with its electric semi-truck. In November of last year, Tesla's semi-truck achieved 500 miles of range with a full load. By comparison, Volvo's electric FM truck has a range of over 235 miles. However, the electric semi-truck race is just as much about cost and availability as it is about specs. Even so, Tesla's progress indicates that the electric semi-truck industry could one day end up being more profitable for Tesla than its consumer cars. But that's a big "if." And in the meantime, it's going to cost a lot of money to scale semi-truck production.

In addition to the semi-truck and autonomous driving markets, there's the opportunity for Tesla to expand its renewable energy generation and storage efforts, which remain a sideshow at this point.

Investors interested in the EV industry are getting a rare opportunity to buy Tesla stock at its lowest forward price to earnings ratio ever. However, the stock is still more expensive today than it was from 2016 to 2019 based on its tangible book value.

TSLA PE Ratio (Forward) Chart

TSLA PE Ratio (Forward) data by YCharts

The company is likely to take market share in a slowdown because it has the balance sheet and operating margin to handle weakening demand better than its EV competitors. That advantage alone justifies opening a starter position in Tesla stock.

But if you're the kind of investor that believes Tesla has a chance to disrupt the autonomous driving industry and take market share across the transportation industry (including the trucking industry), then making Tesla a top-10 -- or even top-five -- holding makes a lot of sense, especially at this price.

Accumulation is a safer approach

Howard Smith: Investors have had high expectations for Tesla over the past three years, and have assigned it a correspondingly high valuation. But for those that believe the company and EV sector will continue to grow, the 65% drop in the stock price in 2022 provides a compelling opportunity to invest in the industry leader. I do believe that, and I did recently add Tesla shares to my portfolio. That doesn't mean it's necessarily a good idea to jump in with an outsized position, however. 

That's especially true with Tesla, since it is in a still-evolving sector and could disappoint investors in the near term. A case in point was its recently announced fourth-quarter vehicle delivery data. The shortfall in deliveries came as demand has been impacted by increasing competition, slowing global economies, and the effects of COVID-19 spreading in China. 

Looking at the bigger picture, however, the company's growth remains strong. Its production increased 47% in 2022 versus 2021. But deliveries only increased 40%, leading investors to believe Tesla might not, in fact, meet its previous projections to average 50% growth over the next few years.

That said, now seems to be a good time to begin buying, or adding to your position. Even if Tesla grows earnings by only 30%, it recently was priced at a price/earnings-to-growth (PEG) ratio of below 1.0 based on 2023 estimates. Accumulating shares makes sense now for long-term investors, but there may be better prices to add more later. That's a good reason not to jump in all at once. 

Tesla is a battleground stock for a reason

As swift and brutal as the Tesla stock sell-off has been, there are valid reasons why Tesla stock deserved to fall. The valuation had gotten nosebleed, to put it lightly. Tesla stock rose 743% in 2020 and then another 50% in 2021 for a two-year gain of -- wait for it -- 1,263%.

Tesla stock could easily set new all-time highs in the future. The problem with stock prices rising so quickly is that the company has to hit lofty goals to make the valuation reasonable. And as impressive as Tesla's growth has been, a mix of macroeconomic and self-inflicted challenges are making those lofty goals increasingly unlikely. Missing delivery expectation paired with the possibility of a recession (and slowing demand for discretionary purchases like cars) adds another layer of issues impacting Tesla. 

In sum, now isn't the time to go all-in on Tesla stock. But it is the perfect opportunity to reassess what your investment thesis for Tesla is, as well as if you want to open a starter position in Tesla or add to Tesla stock now that it's at a reasonable valuation.