Retirees in search of investment opportunities generally try to avoid stocks that have been experiencing wild price swings, companies struggling through significant transitions, or businesses focused on markets where there's little to no growth potential.

Plenty of companies do fit those descriptions, so finding stocks that are a bad fit for retirees' portfolios wasn't a difficult process. Three in particular  that I feel should be avoided by those basking in their retirements are Palo Alto Networks (NYSE:PANW), Hewlett-Packard Enterprise (NYSE:HPE), and Fitbit (NYSE:FIT).

An older man smiling as he grabs his golf clubs.

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Sky-high spending

Usually the first thing Palo Alto bulls -- and there are a lot of them -- point to when justifying their position is the company's top line. Last quarter, it generated $509.1 million in revenue, good for a 27% year-over-year jump.

However, revenue growth is expected to slow to the 21% to 24% range this quarter, putting the top line somewhere between $482 million and $492 million. But the network and enterprise security company's slowing growth isn't what makes its  stock so horrible for retirees: It's the company's continued, rampant spending.

Last quarter's operating expenses were $397.9 million, a staggering 24% increase from Palo Alto's already sky-high spending the year before. The largest expense category was sales costs, which hit a jaw-dropping $245.4 million, nearly half Palo Alto's revenue. Not surprisingly, it reported a $0.42-per-share loss, 20% worse than last year's loss of $0.35 a share. Wild price swings and mounting losses? Not a winning combination for retirees, who are more interested in stability.

Batting .500

It was big news when HP Inc. split from Hewlett-Packard Enterprise two years ago, and rightfully so given that the company was a tech pioneer. The move has paid big dividends for HP Inc., which is now over-delivering in nearly every facet of its PC and printing businesses. The same can't be said for HP Enterprise.

Granted, HP Enterprise has been put through a series of further changes since it was split off, including selling its enterprise services unit and a large part of its software assets. The costs associated with those sales and the ongoing restructuring continue to weigh on its quarterly results, which CEO Meg Whitman is quick to point out.

Unfortunately, the restructuring and other expenses aren't new and will continue to impact HP Enterprise's financials in the foreseeable future. The results is that HP Enterprise's costs and expenses will continue to climb as they did last quarter to $8 billion, well above the $5.36 billion a year ago.

Factor in that the company plans to cut another 5,000 jobs -- 10% of its workforce -- and one can see that, two years into its transition, HP Enterprise's plans to lead the cloud Infrastructure-as-a-Service (IaaS) market aren't working. Based on its shares' 39% drop in value this year, I'm not the only one who has lost confidence in HP Enterprise. Retirees don't need this stock in their portfolio.

Running in place

Fitbit has had its share of hiccups over the past year, most notably when it failed to meet sales expectations for its fitness trackers, which left it with massive inventory surplus it's just now beginning to manage. As disappointing as Fitbit's 40% drop in quarterly revenue to $353.3 million in the most recent quarter was, the reason behind the nosedive is what's really concerning.

Sales in the U.S -- where Fitbit gets more than half its revenue -- were $199 million in the second quarter. Problem is, that domestic revenue number reflected an eye-popping 55% year-over-year decline. Fitbit thinks it may have a solution: its new Ionic smartwatch. As per CEO James Park, the device will be on store shelves before the all-important holiday sales season.

Thing is, casting a line into the smartwatch pool isn't likely to be the answer to Fitbit's woes. The number of fitness devices it sold last quarter (3.4 million)  was well below the 5.7 million it moved a year ago, and now the company thinks its salvation lies in going head-to-head with Apple, the only smartwatch manufacturer showing any signs of success? Fitbit's horrendous sales trend, combined with a strategy that's based on entering the wrong market well behind its competitors, explains why this is a stock retirees seeking stability and growth should avoid.

Tim Brugger has no position in any of the stocks mentioned. The Motley Fool owns shares of and recommends Apple and Fitbit. The Motley Fool has the following options: long January 2020 $150 calls on Apple and short January 2020 $155 calls on Apple. The Motley Fool recommends Palo Alto Networks. The Motley Fool has a disclosure policy.