401(k) & Workplace PlansIf you were auto-enrolled in your 401(k), you're almost certainly in a target-date fund — it's the default in most plans. It's a reasonable default. But "default" and "safe" are not the same word, and the difference lives in the one scenario the fund was never designed to handle: a crash.
A target-date fund follows a fixed glide path — a preset schedule that shifts from stocks to bonds as your target year nears. It never reacts to markets. In 2008, target-date funds built for people retiring in just a couple of years still fell more than 20% because they held course through the crash. The glide path manages your age; it does nothing about the market's worst moments.
What a glide path is — and what it isn't
The glide path is the fund's rule for getting more conservative over time. A 2050 fund holds mostly stocks; a 2025 fund holds far more bonds. That part works as advertised. What surprises people is that the glide path is the only risk control. Within any given year, the fund holds its blend and rides whatever the market does — up or down — without adjusting.
So a near-retiree in a conservative target-date fund is protected against being too aggressive for their age, but not against a bad year arriving at the worst possible time. For more on the trade-off, see convenience vs. cost.
Why timing makes it worse
The danger is concentrated in the five years on either side of retirement — what researchers call the "fragile decade." A deep loss there hits the largest balance you'll ever have, right as you stop adding new contributions and start taking money out. Selling shares for income while they're depressed locks the loss in permanently. A 25-year-old can shrug off a 30% drop; a 63-year-old often cannot.
See the drawdown for yourself
The 401(k) Safety Check lets you build a target-date-style allocation, jump to 2008 or 2022, and watch the drawdown unfold month by month — with a loss-aware model overlaid. You'll see the worst 12-month stretch for each, which is the number that actually matters if you're near retirement. It's a far more useful question than the glossy "average return" on the fund's fact sheet.
A better default is possible
The fix isn't to abandon the funds in your plan — it's to use them with discipline. A rules-based monthly update can trim risk when markets weaken and restore it as they recover, keeping the convenience of a hands-off approach while addressing the one thing a glide path can't. That's the idea behind 401(k) Edge, and what happened in 2008 is the case study.