Devina Mehra’s 90% rule: Why asset allocation matters more than stock tips

Investing is neither as easy as social media nor as intimidating as many fear, but it does demand discipline, balance, and a deep respect for risk. That was the core message delivered by investment firm First Global's founder, chairperson and Managing Director Devina Mehra during the session titled 'Investing for Everyone' at the Mathrubhumi International Festival of Letters.

Drawing from her journey that began in the early 1990s during India's economic liberalisation, Mehra traced how the opening up of markets to foreign institutional investors transformed the country’s financial landscape. At a time when formal securities research barely existed and institutions like SEBI and NSE were yet to be established, she identified the professionalisation of markets as a turning point. Despite being told she did not fit the traditional profile of a stockbroker -- "not a Gujarati, not a Marwari, and a woman" -- Mehra secured membership in the Bombay Stock Exchange, calling it an early lesson in conviction and goal setting.

"If you go deep and focus on quality, your work will stand out globally," she said, emphasising first principles thinking over imitation. However, the session focused less on her success story and more on correcting what she called dangerous misconceptions among new age investors.

Mehra warned against polarised financial behaviour either keeping all savings in fixed deposits or jumping into high risk trading, crypto speculation, and trending stock themes. "SEBI data clearly shows most individuals lose money in trading," she noted, adding that many so called trading "gurus" make money from courses, not markets. Her first rule is to avoid both 100% safety and 100% risk.

Instead, she advocated asset allocation spreading money across equity, fixed income, gold, and real assets calling it the single biggest determinant of long term wealth. "Eighty five to ninety percent of your eventual wealth depends on where your money is allocated, not on stock tips," she said.

Challenging conventional wisdom, Mehra dismissed two widely-repeated rules. First, young investors should not put all their money in equities. Second, retirees should not move entirely to fixed income. The real "superpower" in investing, she said, is the ability to stay invested through volatility without panic selling.

On portfolio rebalancing, Mehra cautioned against excessive market timing. Investors should remain invested but periodically reassess whether their holdings still make sense. Emotional anchors such as waiting for a stock to return to the purchase price are misleading. "The market has zero interest in what price you bought at," she said.

A key theme of her talk was risk control. Citing the concept of "The Loser's Game", she argued that modern investing is about avoiding big mistakes rather than chasing spectacular wins. "Play not to lose", she said, comparing it to amateur tennis where consistency beats flashy shots.

Mehra highlighted global diversification as the biggest gap in Indian portfolios. Currency movements alone can sharply affect overseas education or lifestyle costs, she pointed out. Over time, she suggested, investors should aim for a meaningful international allocation instead of keeping "all eggs in the India basket".

The session concluded with a simple takeaway: wealth grows not from excitement, but from balance, patience, and disciplined risk management . These are the principles Mehra hoped to pass on through the session.