Focus on low-cost equity mutual funds has increased dramatically in the past decade. While cost matters, mutual funds, much like other goods and services, should be evaluated based on what investors get for the price they pay. Indeed, few people start shopping for a car by asking, “What’s the cheapest car I can get?”

The last eight years have been a good period for equity investing. But can it last? As the old saying goes, “Markets climb a wall of worry.” There is certainly plenty to worry about: looming market corrections, elections in Europe, and political uncertainty.

During extended bull markets like we are experiencing now, many investors ask why they need financial advice when it appears that superior performance at a low cost can be found by simply investing in an S&P 500 Index-linked fund.

When the equity market sets a new all-time high, many people become anxious about what will happen next. It turns out that new market peaks are common, occurring 1,144 times from January 3, 1928 through May 31, 2017, or once a month on average.

Most people rely on the mountain chart, a line or area chart which shows the growth of an investment over time, as a basis for evaluating performance. This type of presentation, which emphasizes volatility, timing, and emotionally charged events like 2008 has inherent biases that distort how we view performance and obscures the real long-term probability of a successful outcome.

The current emphasis on low volatility and non-correlated multi-asset portfolios, created by blending equities, bonds and alternatives, can lead to unnecessary over-diversification and result in significant underperformance for long-term investors. Lost in the myopic obsession with volatility and correlations is the overwhelming importance expected returns play in any growth-oriented strategy.