A faster taper “could set the stage for a rate hike at the March 15-16 meeting, although this may be too early from a labor market perspective even if the pace of improvement does remain rapid,” Jan Hatzius, chief economist at Goldman Sachs, wrote in a research note on Monday. Because he and his team think March would be premature, they expect an initial rate increase in June, though they say May is “very possible.”

Bond purchases help juice markets and keep money flowing to borrowers, so slowing them makes for less additional support each month. A higher Fed interest rate would matter even more, denting asset prices and making many types of borrowing more expensive, like car loans, mortgages and business credit. By raising borrowing costs, the Fed could cool demand, allowing supplies to catch up and lowering prices over time.

Raising rates earlier would be a trade-off. Unemployment has fallen swiftly, dropping to 4.2 percent in November, but nearly four million people are still missing from the labor market compared with just before the pandemic began. Some have most likely retired, but surveys and anecdotes suggest that many are lingering on the sidelines because they lack adequate child care or are afraid of contracting or passing along the coronavirus.

If the Fed begins to remove its support for the economy, slowing business expansion and hiring, the labor market could rebound more slowly and haltingly when and if those factors fade.

But the balancing act is different from what it was in previous business cycles. The factors keeping employees on the sidelines right now are mostly unrelated to labor demand, the side of the equation that the Fed can influence. Employers appear desperate to hire, and job openings have shot up. People are leaving their jobs at historically high rates, such a trend that job-quitting TikTok videos have become a cultural phenomenon.

In fact, the at-least-temporarily-tight labor market is one reason inflation might last. As they compete for workers and as employees demand more pay to keep up with ballooning consumption costs, companies are raising wages rapidly. The Employment Cost Index, which the Fed watches closely because it is less affected by many of the pandemic-tied problems that have muddied other wage gauges, rose sharply in its latest reading — catching policymakers’ attention.

If companies continue to increase pay, they may raise prices to cover their costs. That could keep inflation high, and anecdotal signs that such a trend is developing have already cropped up in the Fed’s survey of regional business contacts, called the Beige Book.

“Several contacts mentioned that labor costs were already being passed along to consumers with little resistance, while others said plans were underway to do so,” the Federal Reserve Bank of Atlanta reported in the latest edition, released last week.

Still, some believe that inflation will fade headed into 2022 as the world adjusts to changing shopping patterns or as holiday demand that has run up against constrained supply fades. That could leave the Fed with room to be patient on rate increases, even if it has positioned itself to be nimble.

Lifting rates “before those people come back is a little bit like throwing in the towel,” Ms. Markowska said. “I have a hard time believing that the Fed would throw in the towel that easily.”