As the Federal Reserve prepares to raise interest rates for the first time since 2006, almost all the talk of a potential policy misstep has centered on the peril of hiking too soon.

The bigger concern is that the Fed may wait too long, say Thomas Lam at RHB Securities Singapore Pte. Ltd and David Glocke at Vanguard Group Inc. A decision to keep the overnight rate near zero on Sept. 17 may wind up jolting debt markets more than actually raising it, said Lam, who according to Bloomberg was the fourth-most-accurate forecaster of the U.S. economy last quarter.

The worry is that by holding its target at crisis-period levels too long, the Fed may fail to get ahead of a strengthening economy. That would push up yields as traders anticipate that policy makers will have to adopt a more aggressive approach to lifting interest rates than the gradual path Fed Chairman Janet Yellen has stressed.