It's that time of year when interns pour into offices across the country.

For some workers, this is welcome relief as they now have some extra hands to take care of more menial tasks. For others, this can be a drag as hours and days are spent training folks who may not come back.

Wall Street CEO Rich Handler, who runs investment bank Jefferies, circulated a memo to employees, which Yahoo Finance's Julia La Roche obtained, with a completely different take on what interns bring.

“[I]t might be more important to anticipate and reflect upon what we can learn from them,” Handler wrote as he identified five potential lessons.

"Our interns view this opportunity as the very beginning of a long and successful career," he noted.  "Remember when each of us had that extra glimmer of excitement of what the future could or should hold. They hopefully arrive without battle scars, judgmental opinions, negativity, sarcasm or jadedness."

Indeed, those unfavorable qualities that seasoned workers often develop can be harmful for a company. Handler doesn't say this explicitly, but management certainly considers this stuff when they think about restructurings and turnover. Who needs negative energy poisoning morale when every year there's a new crop of qualified optimists ready to take over?

He went into specific aspects of business, and in particular, customer service.

"The highlight for every summer intern is when they get the chance to have even a brief encounter with one of our clients," he said. "Our interns realize how truly important and vital every client is to each of us ... Because of this understanding, they act with precision, integrity and in a tireless manner every single day."

You don't need negative, jaded employees in the front office.

And so Handler's message isn't relevant for just Jefferies or other investment banks. It's relevant for every workforce in America and perhaps the world.

To be clear, Handler didn't explictly say that anyone in his workforce is necessarily at risk of losing their jobs because of attitude problems.  Rather, he's emphasizing the intangible value that comes with the qualities often possessed by young interns.

"There is no lesson here that is new and in fact most of us live the same way today as we did our very first day," he said.  "That said, sometimes hard work, the passage of time or just living in the real world have a way of causing us to forget a lesson or two."

Yahoo Finance's Julia La Roche first reported on Handler's five lessons.

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Sam Ro is managing editor at Yahoo Finance.

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