Shares of Yelp Inc (NYSE:YELP)Valeant Pharmaceuticals Intl Inc (NYSE:BHC), and Hain Celestial Group Inc (NASDAQ:HAIN) may look attractive to investors right now. Yelp is coming off a subpar quarter, which has its stock down by 22% in the past few weeks, and still has solid growth prospects. Valeant has seen its stock price fall more than 90% from its all-time high and could be an excellent turnaround opportunity. Hain Celestial's shares are down by half from its peak, in the wake of what management says is a minor accounting hiccup. 

But before you pull the trigger, it's important to understand the whole picture, and not just the stock's recent down movement and the possibility of a rebound. There's something to like about each of these companies, but there's also real risk that could send these stocks falling even farther. Keep reading to learn why you may be better off waiting a little longer before you buy Yelp, Valeant, or Hain Celestial. 

Hand reaching towards a stack of cash in a very large rat trap.

There could be opportunity in these stocks, but it may be best to wait a little longer before investing. Image source: Getty Images.

Turnarounds take time

Keith Speights (Valeant Pharmaceuticals): Joe Papa, Valeant Pharmaceuticals' CEO, likes to refer to his company as the "turnaround opportunity of a lifetime." He could very well be right, but there's a long way to go. 

The biggest problem for Valeant is its crushing debt load. The company is making at least some progress on this front. In January, Valeant sold Dendreon to Sanpower Group and three skincare brands to L'Oreal. The two deals combined generated roughly $2.1 billion that is being used to pay down debt.

That's not enough, though. Papa committed to reducing Valeant's debt by $5 billion by early 2018. While Valeant still has plenty of brands it can sell off, they might prove to be more challenging to find buyers willing to pony up the cash Papa would like to get.

VRX Total Long Term Debt (Quarterly) Chart

VRX Total Long Term Debt (Quarterly) data by YCharts.

Valeant must also return to earnings growth. One key to achieving improvement on the bottom line is to grow sales for Xifaxan, which treats irritable bowel syndrome with diarrhea (IBS-D) and travelers' diarrhea. However, Xifaxan has a strong competitor in Allergan's Viberzi.

Another important path to earnings growth lies with brodalumab. The autoimmune disease drug recently won U.S. regulatory approval. However, it faces several big rivals and must overcome the negative implication of carrying a black-box warning for risks in patients with a history of suicidal thoughts or behavior.

Joe Papa might be successful in reducing Valeant's debt and improving earnings, but I think investors would be better off taking a wait-and-see approach. 

This slow-mo decline needs to be reviewed

Rich Duprey (Yelp): The reviews are in, and investors didn't like what Yelp served up in the latest quarter: a menu of slowing sales, declining profits, and missed opportunity.

The review aggregator's fourth-quarter results were respectable, with sales rising 27% from the year-ago period to $195 million, in line with expectations, but the outlook for the first quarter and coming year caused the market to give the stock a thumbs down, and shares tumbled 15% on the news.

Yelp's forecast for the current quarter is likely to be its slowest ever as a public company. As Foolish comrade Rick Munarriz notes, it won't take much of a stumble to turn revenue gains for the quarter into declines -- and that's not as far-fetched as it may seem.

Person using smartphone to order food online.

Yelp reported a decline in mobile app growth last quarter. It might be worth waitin to see if this is a permanent trend before investing. Image source: Getty Images.

The review site said in-app device growth slowed sequentially to 3.3% and was down to 20.3% from 23.7% a year ago. It marks the sixth consecutive quarter the rate of growth has declined. Local advertising accounts also added only 2,800 new ones sequentially, which management said was the result of realigning its sales force and the go-to excuse of every management team that's missing numbers: the election.

All of that is translating into a full-year revenues forecast of between $880 million to $900 million, the midpoint for which was just below analyst consensus estimates, but more importantly also falls short of management's prior promise to hit $1 billion in revenues this year.

I think Yelp has other problems, too, not least of which has been the practice of some businesses to threaten legal action against people who leave negative reviews. While Yelp itself has moved to highlight businesses that try to stifle free speech by initiating lawsuits for fair but critical reviews, it can't help but have a chilling effect on those who'd want to leave an adverse critique.

Management has plans for addressing its slowing business, which it may be able to rectify, but until it can actually prove it's able to do so, I'd wait to buy this stock.

It's hard to value a business if you don't know its financial results 

Jason Hall (Hain Celestial): Hain Celestial hasn't reported its financial results since May 4, 2016 -- nearly 10 months ago. Last August, the company issued a statement that it was delaying the release of its fourth-quarter and fiscal-year 2016 results, after management discovered it may have recognized revenue related to concessions given to vendors in the wrong financial period. 

Man comparing products in a grocery store.

With no updates in nine months, we don't know if Hain has fixed its growth problems. Image source: Getty Images.

Here we are, almost seven months later, and the company hasn't reported its 2016 results, or its first- or second-quarter fiscal 2017 results, which it would have typically done by now. As a Hain shareholder, frankly I'm not overly concerned that the company will have uncovered any serious scandal. It sells food items, and at worst, the company will probably have to revise its reported results for a few quarters, or even a few fiscal years if it has been recognizing revenue improperly for some time. 

Why am I not concerned? Because Hain's cash-flow metrics have remained solid, something that isn't always reflected in GAAP results. 

So, if I'm not worried, why not buy right now? Hain was dealing with some growth challenges when it last reported, and with nearly a year of zero reported results, it's hard to value the business. If you can't value a business, it's probably a bad idea to buy shares. I own Hain shares and still like the company, but a lack of nearly a year's financial results means a wait-and-see is probably the best approach.