Why Warren Buffett Avoids These 3 Types of Companies

Words of wisdom from Warren Buffett on what NOT to invest in.

Minimising your losers is an absolutely crucial part of successful investing. All investors make mistakes, but if you can reduce the number of ‘unforced errors’, the ‘winners’ you hit will really count.

Legendary investor Warren Buffett has offered many insights over the years into what he invests in and why, but, equally, he’s had much to say about what he doesn’t invest in.

Here are three tips from Buffett that could help make you a more successful investor.

Tip #1

Buffett has what he calls a ‘circle of competence’ — a cumulative knowledge of a number of industries built up over the years — and he largely sticks to what he understands. His advice to investors starting out is to begin developing a circle of competence by focusing on “simple, understandable, strong businesses.”

As an example, Buffett has invested in Coca-Cola for many decades. This is a simple, understandable and strong business — and it’ll be doing fundamentally the same thing in five, 10 or 20 years’ time as it’s doing now.

Buffett avoids investing outside his circle of competence. There may be times when you see share prices flying in some industry you don’t understand and other investors coining it. Don’t let envy tempt you away from your circle of competence. It can often end in tears, as it did for many investors in the dot.com bust.

Tip #2

Some businesses are simple and easy to understand but not strong. Companies that require large amounts of capital investment, but which have no durable competitive advantage (such as a monopoly position or brand strength) and thus no pricing power, aren’t strong businesses.

Buffett has singled out commercial airlines as a particularly pernicious example: “The airline industry’s demand for capital ever since that first flight [by Orville Wright] has been insatiable. Investors have poured money into a bottomless pit …”

Of course, some investors have made money by buying and selling airline shares at the right times over the decades. But for Buffett, whose ideal holding period for a stock is “forever“, capital intensive businesses with no durable competitive advantage make no sense as an investment.

Tip #3

The third ‘avoid’ tip of Buffett’s I want to highlight can apply to any company in any industry.

Buffett has said: “We’ll never buy a company when the managers talk about EBITDA [earnings before interest, tax, depreciation and amortisation]. There are more frauds talking about EBITDA. That term has never appeared in the annual reports of companies like Wal-Mart, General Electric, or Microsoft. The fraudsters are trying to con you or they’re trying to con themselves.”

Buffett’s partner Charlie Munger has been equally scathing: “I think that, every time you saw the word EBITDA [earnings], you should substitute the word ‘bullshit’ earnings.”

I might not go as far as Buffett and Munger in never buying a company where directors talk about EBITDA. For example, I will forgive a mention of the term if they also speak upfront and transparently about cash flow. However, routinely avoiding companies where management attempts to make EBITDA the primary measure and focus would doubtless save investors many disasters.

G A Chester has no position in any shares mentioned. The Motley Fool owns shares of General Electric and Microsoft.

More on Investing

resting in a hammock with eyes closed
Energy Stocks

Invest $10,000 in These Dividend Stocks for $700 in Passive Income

These two top Canadian energy dividend stocks can help investors secure high passive income yields from infrastructure and royalties today.

Read more »

Young adult concentrates on laptop screen
Dividend Stocks

A Beginner’s Guide to Building a Passive Income Portfolio

Are you a new investor looking to earn safe dividends? Here are some tips for a beginner investor who wants…

Read more »

container trucks and cargo planes are part of global logistics system
Dividend Stocks

Before the Clock Strikes Midnight on 2025 – TSX Transportation & Logistics Stocks to Buy

Three TSX stocks are buying opportunities in Canada’s dynamic and rapidly evolving transportation and logistics sector.

Read more »

man touches brain to show a good idea
Energy Stocks

2 No-Brainer Energy Stocks to Buy With $1,500 Right Now

Even when oil prices continue to disappoint, these Canadian energy stocks are proving that strong execution and stable cash flow…

Read more »

some REITs give investors exposure to commercial real estate
Dividend Stocks

The Ideal Canadian Stock for Dividends and Growth

Want dividends plus steady growth? Power Corporation offers a “quiet compounder” mix of cash flow today and patient compounding from…

Read more »

Piggy bank with word TFSA for tax-free savings accounts.
Investing

Get Ready for the $7,000 TFSA Contribution Room in 2026

Canadian investors will receive $7,000 of new TFSA contribution space in 2026. Here's what I would do with it.

Read more »

pig shows concept of sustainable investing
Investing

TFSA Investors: How to Catch Up in 2026

Feeling behind? 2026 could be your catch‑up year. Use a TFSA and a simple ETF like VRE to turn stability…

Read more »

top TSX stocks to buy
Tech Stocks

As the TSX Breaks Higher, These Canadian Stocks Look Poised to Win in 2026

Three Canadian stocks with high-velocity growth potential could be among TSX’s winning investments in 2026.

Read more »