The S&P 500 (^GSPC 0.80%) is home to some of the best and most promising stocks you can own on the markets. When stocks in this broad index go on sale, it could be a prime time for investors to consider investing in them. Three S&P 500 stocks that have been crashing this year are attracting the notice of bargain hunters: Walgreens Boots Alliance (WBA 5.39%), Boeing (BA 2.81%), and Intel (INTC 2.19%).

Let's take a look at why these three S&P 500 stocks are struggling and whether you should consider adding them to your portfolio today.

1. Walgreens Boots Alliance: Down nearly 31% year-to-date

Pharmacy retailer Walgreens hasn't been a bad investment for just this year; over the past five years, the stock has lost two-thirds of its value. There are plenty of reasons to be bearish on the stock. Not only has it struggled to grow, but the company's razor-thin margins make it difficult to turn a profit. While it has been diversifying into healthcare with the launch of primary care clinics through its investment in VillageMD, that may only put greater strain on the business and its resources in the future.

Earlier this year, the company slashed its dividend in an effort to strengthen its financial position. The company is also rumored to be looking at selling off assets, including its Boots U.K. pharmacies.

In the trailing 12 months, the healthcare company has incurred an operating loss of more than $2 billion. And with plenty of challenges ahead, this is a stock that I would steer clear of as things can still get much worse for Walgreens, and there's no guarantee they will get better.

2. Boeing: Down nearly 31% year-to-date

Boeing has had a nearly identical decline to Walgreens this year. The reasons for its struggles also go back multiple years. Its planes have been plagued with safety concerns. In 2019, the Boeing 737 Max was temporarily grounded after it was involved in multiple fatal crashes, and there were reports of issues with engines, wiring, and the flight control computer. Earlier this year, the company made headlines again after a door flew off during a flight. It was later discovered that bolts meant to hold the door in place were missing.

The big issue with the company is trust. Trust that it can deliver quality planes which airlines and passengers can rely on. Changes are coming to the management with CEO Dave Calhoun stepping down this year. If the company makes significant improvements to its quality control, then there's hope that the business may regain the trust of all its stakeholders, including investors.

In the meantime, the business's financials are underwhelming, to say the least. In three of the past four quarters, Boeing has incurred an operating loss. Revenue for the first three months of 2024 declined by 8% to $16.6 billion.

The company faces a tough road ahead, and with a potential slowdown in travel demand amid a recession, there are plenty of reasons why things could still get worse for Boeing. Investors may be better off taking a wait-and-see approach with the stock as the risk surrounding Boeing makes it a bit too risky to invest in the business just yet.

3. Intel: Down 38% year-to-date

The S&P 500's worst-performing stock thus far is Intel, as shares of the chipmaker are down 38% this year. The tech company is positioning itself as a big player in next-gen chipmaking, but that isn't enough to win over investors. CEO Pat Gelsinger says, "We are one of two, maybe three, companies in the world that can continue to enable next-generation chip technologies."

The problem is that generating those chips may not be easy, despite what should be strong long-run demand. For the period ending March 30, Intel's foundry revenue declined by 10% year over year to $4.4 billion. And that area of its business also incurred a loss of $2.5 billion.

Investors appear to doubt the tech company's ability to be a serious player in next-gen chips, given its underwhelming financials. But of the three stocks listed here, Intel may be the more intriguing contrarian play due to the need for the U.S. to reduce its dependence on foreign chipmakers. The U.S. government has agreed to give Intel up to $8.5 billion in grants to help increase chip production in the country, plus another $11 billion in loans.

Although Intel faces an uphill battle and it's still a risky buy right now, it could make for a good contrarian pick given the support it has from the government and the need for domestic chipmaking capabilities.