All investors crave simplicity. That can come at a high cost.

Many investors look at the title of the investment but don’t look under the hood.

A prime example is target date funds. These investments are one of the fastest growing investment products in history. According to the Investment Company Institute, more than $1 trillion is invested in target date funds.

A target date fund is is invested based on your retirement date. Essentially the only thing the investment manager knows about you is your age. But are all 52 year olds the same? Maybe some are skinny and some are fat. Some have plenty of money and some can barely rub two nickels together. Some will retire before 65 and some afterwards. Some will work part-time and some will retire in Central America. Few are average but that’s what target date funds assume.

It’s important to know a lot about an investor to decide how to invest for him. Otherwise you might take too much risk or not enough and returns and investors’ piece of mind might suffer.

Even more compelling, each target date fund is different. Investment managers have different ideas about how to invest for the average 52 year old.

It’s OK to invest in a target date fund but make sure you look at more than just the name. Otherwise, you may learn too late that you and the investment manager had different ideas about what was good for a 52 year old and the consequences may not be pleasant.