WASHINGTON — The U.S. economy is churning out a lot of jobs these days but not a lot of financial security for many of the people who hold them.

Pay growth, though improving, remains tepid. Many workers have few opportunities to advance. Others have taken temporary, part-time or freelance jobs, with little chance of landing full-time permanent work with benefits.

As a result, many jobs don’t deliver as much economic punch as they used to. Part of the reason is that U.S. workers have grown less efficient in recent months. When they produce less per hour of work, their earnings power shrinks. So the economy doesn’t fully benefit from the fuel that healthy job growth normally provides.

The result is a disconnect between the high number of job gains and a nagging dissatisfaction among some, both job holders and job seekers.

Lena Allison lost her job as a private-school kindergarten teacher in layoffs in September. Allison, 54, of Los Angeles has since worked temp jobs and struggled to find permanent work. Online job listings, she says, have made it hard to get face-to-face interviews.

“More people may be working jobs, but they’re like these serial part-time jobs,” she said. “They’re not life-supporting jobs.”

Allison’s experiences, shared by millions of other workers, contrast with the economic momentum suggested by the May jobs report released Friday. The government added a solid 280,000 jobs. The unemployment rate ticked up slightly to 5.5 percent, but for a positive reason: More people decided to start seeking a job, and some didn’t find one.

Many analysts and investment managers cheered as average hourly wages rose at an annual rate of 2.3 percent from 2.2 percent in April, slightly ahead of inflation.

“Not only are the labor markets stronger today than at any point in the past 20 years, but we are beginning to see the start of broad-based wage growth,” said Rick Rieder, chief investment officer for fundamental fixed income at BlackRock.