Earnings season has brought its usual volatility, with some stocks surprising to the upside and others disappointing investors.

There's a great deal of near-term uncertainty facing Tesla(NASDAQ: TSLA), Aspen Technology (NASDAQ: AZPN), and Enphase Energy(NASDAQ: ENPH). However, all three growth stocks could be worth buying on sale for investors willing to ride out volatility and focus on the big picture. Here are the thoughts of three Motley Fool contributors:

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Tesla is built to endure

Daniel Foelber (Tesla): Over the last five years, Tesla's stock has delivered a staggering 767% return. The best time to buy the electric vehicle (EV) leader over the last decade was during its initial public offering (IPO). But another incredible opportunity came in the summer of 2019 when the stock was crashing and fell below a split-adjusted $13 a share -- if you can believe it.

It was a time when few believed production of the Model 3 could be scaled up. Tesla was also losing money, its balance sheet was in disarray, and the company seemed distracted by other projects instead of focusing on the Model 3. Still, buying the stock then was a speculative and highly uncertain bet that the company would reach profitability before it ran out of money.

Today, Tesla is a completely different business. It is free-cash-flow (FCF) positive, has industry-leading operating margins, its balance sheet is arguably the best of any automaker, and there are lots of potential growth outlets other than cars. Down over 58% from its all-time high, the stock now presents a compelling risk/reward opportunity.

Tesla has changed the auto industry. The launch of several pure-play EV companies, not to mention legacy automakers pouring billions into EVs, has left Tesla as the industry's leader. It is in the driver's seat, while other companies struggle to catch up.

Tesla faces increased competition and potential price wars. But it has already climbed the industry's biggest hurdle: making a profit from EVs. In the first quarter, Ford (NYSE: F) lost a reported $722 million from its EV unit. Similarly, General Motors(NYSE: GM) is in the process of scaling up EV production and investing in a reliable battery supply chain. It doesn't expect to make money from EVs until 2025.

Ford and GM could still be good stocks to buy. It's just that in many ways, Tesla is simply a better business at this time for investors who believe in an EV future.

If consumer spending falls and automakers are pressured to cut prices, Tesla should be in the best position to weather the storm. With a forward price-to-earnings (P/E) ratio of 48.6, it is not a cheap stock. But it is an excellent company that has a clear growth runway for the next decade and beyond. And for that reason, the stock is worth buying now.

This industrial software company is going places

Lee Samaha(Aspen Technology): The market hammered Aspen Technology's stock after its disappointing third-quarter 2023 earnings report. The company was created from the merger of the former AspenTech (a maker of software to help optimize industrial assets) and a couple of businesses (in geological-simulation software and power-industry automation software) from Emerson Electric.

The combination was good because of AspenTech's focus on heavy industries -- its main end markets are energy (mainly downstream), chemicals, engineering, procurement, and construction.

It's no surprise to see investors favoring the company, given these end markets and the strength in energy markets over the last year (matched by higher capital spending), and the increasing importance of industrial software in helping customers use their assets effectively.

Unfortunately, the stock's strong run over the last few years came to a crashing halt recently as management lowered its full-year guidance for revenue, earnings, and free cash flow. That downgrade comes on the back of demand weakness from chemicals customers pressured by high energy costs, a slowing economy, and ongoing supply chain challenges.

This looks like some cyclical weakness (admittedly exacerbated by high energy costs) in an otherwise solid secular growth market. The benefits of using software to gather data to optimize performance and better maintain assets will only improve in the digitally connected age. Despite the hiccup, Aspen Technology is well prepared for long-term growth.

There may be clouds now, but Enphase will shine over the long term

Scott Levine (Enphase): Year-over-year revenue growth? Check. Gross margin expansion? Yes. Net income growth? Yup, that too. But these glowing details in Enphase's first-quarter 2023 earnings report weren't enough to satisfy investors, leading to a steep sell-off in the stock.

Instead, they focused acutely on the fact that the provider of microinverters for residential solar systems failed to meet analysts' top-line expectations. Analysts' second-quarter revenue estimate of $773 million is below the company's forecast of $700 million to $750 million for the quarter, which also failed to charge up investors' enthusiasm.

While the market was clearly disappointed with Enphase, it's important for long-term investors to recognize that it didn't report anything that hints at something fundamentally wrong with the company. The stock's sell-off, moreover, isn't shocking as shares have consistently traded at a high valuation.

Its five-year average P/E ratio, for example, is 138, so with management forecasting second-quarter revenue growth lower than analysts' expectations (albeit still considerable on a year-over-year basis), investors overreacted and clicked the sell button.

On the brighter side, patient investors would be wise to consider warming up to a leading solar stock like Enphase. The company is consistently expanding into global markets -- most recently Spain, Portugal, and Australia -- as well as increasing its offerings to U.S. residential customers. And the passage of the Inflation Reduction Act provides a notable tailwind for the domestic market.

One of the most auspicious signs that the stock has a bright future is a recent insider stock purchase. On April 26, Thurman Rodgers, a member of the board of directors, bought 32,900 shares in a transaction valued at more than $5.4 million.

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Daniel Foelber has positions in Enphase Energy and has the following options: long June 2023 $155 calls on Enphase Energy, long June 2023 $190 calls on Enphase Energy, long September 2023 $146.67 calls on Tesla, short June 2023 $150 calls on Enphase Energy, short June 2023 $160 calls on Enphase Energy, short June 2023 $195 calls on Enphase Energy, and short September 2023 $150 calls on Tesla. Lee Samaha has no position in any of the stocks mentioned. Scott Levine has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Emerson Electric and Tesla. The Motley Fool recommends Enphase Energy and General Motors and recommends the following options: long January 2025 $25 calls on General Motors. The Motley Fool has a disclosure policy.