Warren Buffett's former deputy just published her first annual letter since quitting to build her own Berkshire Hathaway. Here are the 10 best quotes.

• Warren Buffett's protégée left Berkshire Hathaway to start her own company, Kanbrick.
• Tracy Britt Cool and her cofounder published their first annual letter this week.
• They underscored their long-term view and warned easy money is distorting markets.
• See more stories on Insider's business page.

Warren Buffett's former deputy, who quit Berkshire Hathaway to build her own conglomerate last year, just published her first annual letter.

Tracy Britt Cool was hired as Buffett's financial assistant in 2009, went on to chair several Berkshire businesses, and served as CEO of another one, Pampered Chef. She partnered with her former CFO, Brian Humphrey, to found a long-term investment firm called Kanbrick last April.

Kanbrick closed its first deal last summer, securing a stake in Thirty-One Gifts. It recently rolled out "Build with Kanbrick," a three-month support program for the bosses of mid-sized businesses.

Britt Cool and Humphrey's letter echoes Buffett's yearly missives to his investors over the past six decades. They clearly share the Berkshire chief's long-term focus, passion for educating others, knack for entertaining readers, and willingness to sound the alarm when needed.

Here are the 10 best quotes from the letter, lightly edited and condensed for clarity:

1. "The name Kanbrick is a nod to our shared experience growing up in Kansas and our belief that great things are built 'brick by brick' - day by day, little by little, through hard work, discipline, and integrity. This is in our DNA, and we lived this every day growing up and working in our family businesses - farming for Tracy and cabinetry for Brian."

2. "Great companies are not built in spreadsheets, and we create value through building enduring companies vs financial wizardry and loads of debt."

3. "We stay away from macro predictions like foreign exchange or interest rates - our Magic 8 ball hasn't been helpful, and, despite years of searching, we have yet to find a crystal ball."

4. "Based on our research and personal experience, we believe the combination of Purpose, People, and Performance drives results. This three-legged stool is rarer than a four-leaf clover - most companies only focus on one or two areas and few deliver on all three."

5. "If setting out on a 100-mile road trip, then you'd want more than 100 miles' worth of gas (especially if you're traveling through western Kansas where gas stations are rarer than cows)." - describing how they apply a "margin of safety" to their annual plan.

6. "The crucible of capitalism craves efficiency - customers always want better products faster and at lower prices - and the dust heap of history is littered with formerly iconic firms such as Polaroid and Blockbuster. COVID is another reminder that we can't predict the next crisis; however, we know dark clouds and stormy seas will appear again in the future."

7. "While many investors look to run a three-year sprint, we are running a marathon and are comfortable leaving some gas in the tank (and giving up some short-term gains) to ensure we can finish mile 26 strong."

8. "Moats and sources of competitive advantage evolve and erode over time. Newspapers used to have an enviable moat, but we all see how the water there has dried up."

9. "The current low-rate, high-stimulus environment seems to have distorted incentives and market signals." - Kanbrick and Humphrey warned that the long-term impacts of government aid for ailing businesses are unclear, and cautioned that low interest rates are boosting asset prices and "numbing investors to potential risks."

10. "Eventually each business' value must be anchored in the cash it produces."