Professionally managed target-date funds, of course, have one goal: A glidepath suitable for getting workers into retirement, then allowing them to draw down assets over a 30-year time horizon. But many retirees, wrote Bruno, “have other situations or goals and could result in a different target asset allocation.”

So what might some of these other goals be?

Bruno said retirees might be aiming toward other goals than just retirement — such as “managing the risks of not outliving their retirement portfolio” or “maximizing wealth transfer opportunities.” Such goals, she said, compel retirees “to consider factors such as market uncertainty, inflation, and increasing life expectancies.’

Then there are retirees who are using their portfolios more or less as cash cows, using them for spending money rather than trying to spend them down. Such a mindset, Bruno pointed out, could lead them to keep the portfolio balanced in an effort to preserve the real value of their assets.

There are always some who don’t rebalance, whatever their goals — or who are reluctant to abandon a rising market in the name of “selling winners to buy losers.” A drop in the equity market is of less concern to many of these than the potential for interest rate increases, and they’d rather stay where they are than rebalance.

And last but not least, Bruno cited affluent retirees who intend to leave their IRAs as an inheritance for children or grandchildren, and who are therefore determined to grow the balances as much as possible and to take advantage of longer drawdowns granted to younger IRA beneficiaries to let equities with the greatest growth potential simply — grow.

That could be particularly true in the case of Roth IRAs, since Roth IRA owners aren’t subject to required minimum distributions during their lifetimes. That means that those assets pass income-tax-free to future generations, making them particularly apt legacies.