Buy low, sell high. It’s an investing mantra drummed into our heads from the moment we start buying stocks. But it’s not easy to do. When our stocks start falling, the first inclination for many investors is to sell. We no longer see them as turnaround stock picks. These are the biggest stock losers that turned it around and are now worthy of your investment.

Yet if you liked the stock at $20 a share, you should love it at half price. We like buying shirts when they go on sale, but we have an aversion to buying stocks when they give us the equivalent of a buy one, get one free discount.

Although we should aim to hold our stocks for the long-term, there are times when it makes sense to sell quickly. Even Warren Buffett who professes a buy-and-hold mentality, sometimes dumps shares soon after buying them. He bought boatloads of Taiwan Semiconductor Manufacturing (NYSE:TSM) stock early last year only to completely sell off his stake less than a year later. That hardly seems to be the actions of someone who once said, “the best time to sell is never.”

Yet Buffett will sell when his investment thesis is broken. He never really said why he quickly moved into and out of the semiconductor stock, but saber-rattling between China and the U.S. over Taiwan could have been a motivating factor.

What follows are three stocks that crashed and burned in November. Shares fell 33% or more for the month. Is now the time to scoop them up in hopes of a major recovery? Let’s dig in to see whether there is hope for a turnaround or if they deserve to be the biggest stock losers.

ECARX Holdings (ECX)

Digital cockpit supplier ECARX Holdings (NASDAQ:ECX) saw its stock tumble 33% in November despite reporting rising sales, narrower losses, and a plan to become profitable in the next few years. There are 5.6 million vehicles on the road with ECARX technology in them and it has several new customer wins under its belt. The direction ECX stock is taking seems counterintuitive for the improvements being reported.

The problem for ECARX is that most of its gains are mostly through related-party transactions. The auto parts stock is closely affiliated with the Chinese automaker Geely (OTCMKTS:GELYF). Most of its sales have been to Geely. ECARX co-founder Eric Li also the founder of Geely and head of several Geely-related automakers including Volvo (OTCMKTS:VLVLY) and electric vehicle (EV) maker Polestar (NASDAQ:PSNY). 

Many of the new customer wins were to Volvo and Polestar. Although ECARX is trying to expand beyond Geely’s orbit, it’s having difficulty going beyond the Chinese automaker’s gravitational pull. Even when it does score deals with international carmakers such as Mazda (OTCMKTS:MZDAY) and Stellantis (NYSE:STLA), it’s for vehicles being made for the Chinese market. Its partnership with Mobileye (NASDAQ:MBLY) to develop a fully integrated driver-assist solution is for the Polestar 4 SUV.

The China market is a large and growing one, but the tight circle ECARX travels in is a risk. So far it’s unable to capitalize on its global ambitions. Still, ECARX business is growing so it might be worthy of investor attention at these valuations. However, don’t buy a big tranche of stock. Only put a small amount in the high-risk section of your portfolio. Once its in your portfolio, you will see why it was worth it despite being one of the biggest stock losers.

Acelyrin (SLRN)

Biotech Acelyrin (NASDAQ:SLRN) was severely kneecapped in September after reporting disappointing results in a clinical trial evaluating the efficacy of its experimental lead drug, izokibep. The inflammatory skin disease therapy did not meet statistical significance in a phase 2b/3 trial. That took Acelyrin’s stock from around $28 a share down to about $12 a stub.

They tumbled again in late November after the biotech said the earlier failure was due to a programming error in clinical trial protocols by a ​​vendor of its contract research organization (CRO) for the programming error. Acelyrin is trying to take on pharma giants Eli Lilly (NYSE:ELY) and Novartis (NYSE:NVS) whose Taltz and Consentyx, respectively, dominate the market. Acelyrin was down 34% for the month as a result.

The CRO is Fortrea Holdings (NASDAQ:FTRE) that was recently spun off from Labcorp. It disputed some of the allegations made by Acelyrin, and was conducting an audit of the issue as was the biotech. Acelyrin, though, has said it will never use Fortrea again for any of its trials. It may also transition its existing trials to a new CRO as well.

The rough and tumble of biotech testing makes investing in such stocks a crapshoot as it is. Major failures like this can be devastating, particularly with a newly IPO’d stock like Acelyrin. Because it’s hard to know whether the CRO’s programming error was the cause of the trial failure or the drug itself didn’t live up to is promise, it’s hard to recommend an investment in SLRN stock even at these depressed levels. This one easily earned its spot on our list of the biggest stock losers worth grabbing now.

Fisker (FSR)

Luxury EV maker Fisker (NYSE:FSR) is another stock that was already heading to the cellar before November hit. It only continued its path lower during the month, dropping another 65%. The slide began last month after reporting another quarter of disappointing earnings. It snowballed further after the EV’s chief accounting officer resigned just two weeks after accepting the job. It serves as a warning sign to investors.

Fisker struggled to sell its cars in the third quarter. While it delivered 1,097 vehicles for the period revenue was still far below what analysts expected. However, it sold more in October than at any time during the rest of the quarter. Yet Fisker generated $71.8 million in sales, a far cry from the $109 million Wall Street was looking for. Losses of $0.27 per share were also much worse than the $0.19 per share analysts forecast.

Perhaps worse for the automaker was it cutting its production target for the full year. Where it had originally guided towards producing 20,000 vehicles this year, it slashed it to a range of 13,000 to 17,000 vehicles.

It’s tough to sugarcoat Fisker’s dire situation. The EV maker is rapidly burning through the little cash it has on hand. At the end of the third quarter, Fisker had $527 million in cash and equivalents but operating activities used $308 million. It was also almost $1.2 billion in debt.  

Fisker says it raised $450 million in cash during the quarter and was waiting on $50 million in VAT receivables. It also has some $550 million available in gross proceeds from a convertible notes transaction. 

Fisker might not go bankrupt (again) anytime soon, but that doesn’t make it a stock to put your money into. If you are looking for the biggest stock losers that you should grab now, this one is perfect.

On the date of publication, Rich Duprey did not hold (either directly or indirectly) any positions in the securities mentioned in this article. The opinions expressed in this article are those of the writer, subject to the InvestorPlace.com Publishing Guidelines.