In 1919, as the White and Red armies fought a brutal, seesaw war for control of Russia, British War Secretary Winston Churchill prodded his government to commit troops to the fight.

The Bolsheviks, he declared, were “swarms of typhus bearing vermin.” They “hop and caper like ferocious baboons amid the ruins of their cities and the corpses of their victims.” Churchill’s rhetoric was so inflammatory that, after he addressed the House of Commons on the topic, Tory Party leader A.J. Balfour felt compelled to comment. With quintessential British coolness, the former Prime Minister told the future Prime Minister, “I admire the exaggerated way you tell the truth.” 

Unfortunately, exaggerated truth-telling is as commonplace in business as in politics. Walter Isaacson cites Steve Job’s “reality-distortion field” repeatedly in his go-to biography of the Apple’s mercurial chief. “[Jobs] would assert something—be it a fact about world history or a recounting of who suggested an idea at a meeting—without considering the truth,” writes Isaacson. He would conjure up an impossible production date, for instance, and demand it be met. Surprisingly, as Isaacson recounts, it often was.

Elon Musk seems to have picked up Job’s penchant for exaggerated truth-telling. Musk says that Tesla’s factory in Fremont, CA will produce as many as 500,000 vehicles in 2018—an “extraordinary leap in production” from less than 84,000 in 2016, according to Jeff Rothfeder’s insightful analysis in The New Yorker. Can Musk’s employees and suppliers deliver on his promise or is this exaggerated truth-telling? Well, as The Wall Street Journal calculates it, Tesla has missed Musk’s projections more than 20 times in the past five years.

The problem is that exaggerated truth-telling is a two-edged sword. If your exaggerations can be transformed into reality, you’re a hero. If not, you’re on a slippery slope. If she didn’t know that before, Elizabeth Holmes should know it now that her $4 billion stake in Theranos, the company she founded to disrupt blood testing, has evaporated and the lawsuits are piling up. So, too, should Josh Tetrick of Hampton Creek and the leaders of Volkswagen.

Winston Churchill was, of course, one of the greatest communicators of the 20th century, and business leaders can learn a lot from his rhetorical prowess. But as you study him, keep this in mind: When University of Exeter historian Richard Toye examined contemporaneous reactions to the WWII speeches that are the most cited evidence of Churchill’s reputation as a communicator, he found that they did not produce “unanimous or near unanimous rapture” in the British people.

Plenty of listeners found them depressing and alienating—especially when the news of the war was bad. The greatest value in Churchill’s WWII speeches turned out be the information and perspective they communicated. Even Churchill’s formidable command of language was “no substitute for meaningful content,” concludes Toye.

This finding might explain why the British government ignored Churchill’s exaggerated truth-telling in 1919 and withdrew from Russia, rather than escalate its involvement in the fight against the Bolsheviks. It also should give today’s business leaders pause as they craft their own communiques.