Investors have conflicting ideas about what they want when it comes to risks and returns, according to a study by AssetMark.

Ninety-five percent of mass affluent investors claim they are in the market for the long term, but 58 percent expect their advisors to change their investments frequently to keep up with changing market conditions, says the AssetMark Mass Affluent Investor Risk Barometer, released Thursday.

The study included 501 investors with investable assets of $250,000 to $1 million between the ages of 30 and 70 who work with a financial advisor and are primary or shared decision-makers regarding investments.

Ninety percent of respondents say they are looking for growth or growth and income and yet 68 percent are more concerned about the safety of their investments than about maximizing returns, according to AssetMark, a provider of consulting and investment resources for advisors.

The study also revealed that 75 percent of respondents expect their investment portfolios to increase by 12 percent, despite the average return of 7.7 percent over the last 10 years for the S&P 500. Sixty-five percent have kept the same amount of risk in their portfolio since 2008.

"We found that investors expect more from their portfolios than is realistic and this can cause some dissatisfaction," says Zoe Brunson, AssetMark's director of investment strategies. "For instance, investors reported that the size of their portfolio, on average, had increased 14.2 percent last year and 48 percent were not happy with their 2014 returns year-to-date."

"It's critical that advisors set the right expectations with their clients. Focus on building a portfolio to meet client goals rather than chasing last year's winner. Aim to be balanced across strategies that do well in rising markets and strategies that also do well in falling markets," Brunson adds.

The study findings are reinforced by advisor sentiment, says AssetMark.

"More than half of the advisors polled at our recent Premier Consultant meetings indicated that ensuring that clients understand the tradeoff between risk and reward is the largest challenge they face when it comes to meeting client expectations this year," says Charles Goldman, president and CEO of AssetMark.