Brian Feroldi Profile picture
Aug 6, 2023 15 tweets 6 min read Read on X
I've been investing for 19 years.

Here are 10 painful investing lessons I learned the hard way: Image
1: You don't need leverage

Margin & options are fun on the way up, but BRUTAL on the way down.

I’ve lost more than 100% on investments before.

Why? Leverage.

Buffett & Munger said it best:
Image
Image
2: Optimize for longevity, not upside

Compound interest is the most powerful wealth-building force that exists.

But it only works if you SURVIVE long enough for it to work.

I used to optimize for upside. Now, I use the barbell method to optimize for longevity. Image
3: High conviction does not mean I'm correct

I convinced myself several times that a stock could only go up.

I was right on some. On others, I lost 70% (!!)

Conviction is useful, but just because you think you are right doesn’t mean you are.

Allocate accordingly.
4: Stock prices & business results are 0% correlated in the short-term and 100% correlated in the long-term

I’ve sold future mega-winners because their stocks were down (dumb).

I was watching the stock, not the business.

Now, I do the reverse. Image
5: Not having a system

I used to keep everything in my head, which was dumb (and impossible).

I didn't use checklists, journals, or watchlists, which are invaluable free tools.

This caused me to make tons of mistakes.

Now, I have a system: Image
6: Not understanding valuation

I passed on high p/e ratio stocks (that went up big).

I bought low p/e ratio stocks (that went down big).

Why? I didn’t understand the business growth cycle.

Now, I know WHICH valuation metrics to use (and WHEN to use them). Image
7: Panic selling and panic buying

My emotions have caused me to panic buy hype stocks and panic sell future mega-winners.

It’s easy to say you’ll be greedy when others are fearful, and visa-versa.

It’s damn hard to actually do it. Image
8: I didn't study history

Human nature is remarkably consistent. The same forces that drove markets 100+ years still exist in all of us today.

There’s always a smart-sounded reason to sell.

I didn't understand that. Now, I do. Image
9: I focused on what I can't control

I used to follow stock prices + the news closely, watching for clues to predict the market.

This was time poorly spent. Macro factors matter, but I have no control over them.

I now focus far more on what I can control. Image
10: Not changing my mind

This one is REALLY hard, but it’s necessary to do well.

Changing your mind is hard. Admitting you're wrong is hard.

But @JeffBezos said it best: Image
I learned all of these lessons the expensive way.

Want to fast-track your learning?

Join me tomorow for my LIVE course, Valuation Explained Simply.

Interested? DM me for a coupon code.

https://t.co/FN0VAheL4Gmaven.com/brian-feroldi/…
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Last one:

Stay humble yet optimistic.

If you invest, you're going to be wrong. A lot.

Don't beat yourself up. That's just how you get better.

Saving money is hard. Investing is hard. The world is complex.

Invest & stay optimistic anyway. Image
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More from @BrianFeroldi

Sep 6, 2025
Tangible vs Intangible Assets.

What's the difference?

Here's everything you need to know: Image
They confused me until I discovered an easy way to distinguish them:

𝗧𝗮𝗻𝗴𝗶𝗯𝗹𝗲 𝗔𝘀𝘀𝗲𝘁𝘀 𝗖𝗮𝗻 𝗕𝗲 𝗧𝗼𝘂𝗰𝗵𝗲𝗱

𝗜𝗻𝘁𝗮𝗻𝗴𝗶𝗯𝗹𝗲 𝗔𝘀𝘀𝗲𝘁𝘀 𝗖𝗮𝗻'𝘁 Image
Another major difference.

- Tangible assets are depreciated

- Intangible assets are amortized Image
Read 6 tweets
Aug 31, 2025
How to analyze an Income Statement, FAST.

Warren Buffett’s 8 Income Statement 'Rules of Thumb': Image
1: Gross Margin

🧮 Equation: Gross Profit / Revenue

👍 Rule of Thumb: 40% or higher

🤔 Buffett's Logic: A consistently high gross margin signals that the company isn’t competing exclusively on price. Image
2: SG&A Margin

🧮 Equation: SG&A Expense / Gross Profit

👍 Rule of Thumb: 30% or lower

🤔 Buffett's Logic: Wide-moat companies don’t need to spend a lot on overhead to operate & convince consumers to buy. Image
Read 11 tweets
Aug 30, 2025
Some stocks are STRONG BUYS when they fall

Other stocks are SELLS when they fall

How can you tell the difference?

Watch for these 5 financial yellow flags: Image
1) GOODWILL WRITEDOWN

This represents the premium a company pays for an acquisition above its fair market value.

If there’s a major goodwill write-down on the Income Statement, it means management has wasted a TON of capital. Image
2) GROSS MARGIN DECLINING

1: The competition is forcing me to lower prices
2: Demand is weak
3: My suppliers are raising prices

Either way, it can be a thesis-busting development Image
Read 9 tweets
Aug 29, 2025
Capitalism is brutal.

If you invest, you MUST know how to identify a moat.

Here are 9 financial “rules of thumb” that Warren Buffett uses to tell if a company has one: Image
1: Gross Margin

Found: Income Statement

Formula: Gross Profit / Revenue

Moat: Consistently above 40%

No Moat: Under 40% & volatile Image
Buffett’s logic:

A consistently high gross margin signals that the company isn’t competing exclusively on price.

A high gross margin also provides ample gross profit to pay expenses and leaves money for shareholders.
Read 22 tweets
Aug 27, 2025
How to analyze an income statement in less than 2 minutes: Image
The income sheet is one of the three major financial statements.

It shows a company’s:
▪️Revenue (Sales)
▪️Expenditures (Costs / Expenses)
▪️Net Income (Earnings, Profits)

Over a period of time. Image
Management teams have leeway in categorizing their income statement.

This means that not all income statements look the same.

Here is a typical layout and the meaning of the most commonly used terms: Image
Read 11 tweets
Aug 26, 2025
Financial Statements For Beginners

Want to learn accounting?

Study these 9 simple infographics (a visual thread) ↓ Image
Image
Financial Statements DO NOT have a universal layout

Here are some other balance sheet terms you might see: Image
Read 9 tweets

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