NEW YORK — Brian Williams had been a trusted voice in news for decades, until questions arose last week about his credibility when he admitted he embellished a story he covered in Iraq.

Some speculate that the NBC news anchor started telling tall tales to appear more interesting as he made the rounds on the late-night talk shows. Others suggest he caved to the pressure to sound anything but boring in an insatiable social media-driven society.

Williams was suspended Tuesday by the network for six months for stretching the truth, a stunning fall from grace, but he’s far from alone. Puffing up one’s experiences — whether it’s falsifying a resume or exaggerating stories to amplify the derring-do factor — is something that everyone does for myriad reasons, whether they admit it or not, experts say.

“Any human being who tells you they have never embellished their own life story is probably lying,” said Bob Thompson, a professor of popular culture at Syracuse University. “My story of how hard it was to get home in the snow on Monday is a lot better on Wednesday. There are all kinds of new things, like abominable snowmen.”

Williams had claimed in numerous reports and appearances that he was riding in a helicopter that was hit by a grenade. But last week, when he was exposed, he admitted that another helicopter — not his — was struck.

There’s an irresistible temptation to improve upon a story and make it more dramatic that dates back to the telling of “The Iliad,” one of the first stories in Western civilization, Thompson said. In recent years, examples of politicians in particular fibbing about their experiences abound.

Hillary Rodham Clinton later said she misspoke after claiming on the presidential campaign trail in 2008 that she landed in Bosnia under sniper fire in 1996, a memory that turned out to be untrue. Also in 2008, Vice President Joseph Biden said his helicopter was forced to land by al-Qaida in Afghanistan. In reality, the chopper made a speedy landing because of a snowstorm.

The Williams debacle is a classic example of people using counterfeit credentials to demonstrate their relevancy and to spin their own personal narrative in order to stay in the limelight, said Matthew Randall, executive director of the Center for Professional Excellence at York College of Pennsylvania. It’s a sign of professional insecurity, sometimes prompted by other competitors on their heels, Randall said.

People usually embellish their credentials by falsifying information on their resumes or LinkedIn profiles — or they tell tall tales at cocktail parties about what they’ve done in the past.

“Typically if a half-truth worked well once, the professional will continue to leverage it and bake it into their professional narrative,” Randall said. “Hence, Williams’ fib had become part of his career.”

It’s also possible that Williams actually believed what he said as the story evolved over the years, according to some experts who say it’s normal for memories to change as time passes. We all change our memories to fit with constantly evolving societal norms: sharpening the details that we’re comfortable with and forgetting the ones that are inconvenient or uncomfortable, said Harold Takooshian, a psychology professor at Fordham University.

“So the bottom line is that Brian Williams is 100 percent normal: It seems to me he was just exaggerating and he started believing what he said,” Takooshian said. “It’s just surprising he wasn’t challenged earlier.”

But journalism doesn’t allow for any smudging of the facts. It’s about scraping away all of that fabrication, all of “that stuff that is part of human nature,” Thompson said.

Journalists can either tend toward narcissism or humility by training their gaze on their subjects or on themselves, said Andrew Harris Salomon an assistant professor of journalism at Purchase College in Purchase, New York.

“Journalists do run a risk of wishing to bathe in the illumination of the people they cover,” said Rich Hanley, an associate professor and director of graduate journalism at Quinnipiac University. “We’re always interlopers in that we cover other people but when we see the light shining there, we want sometimes to be part of that illumination or part of that parade.”

Associated Press writer Jim Fitzgerald in White Plains, New York, contributed to this report.