"Politeness and civility are the best capital ever invested in business," Barnum writes. "Large stores, gilt signs, flaming advertisements, will all prove unavailing if you or your employees treat your patrons abruptly. The truth is, the more kind and liberal a man is, the more generous will be the patronage bestowed upon him."
Barnum should have extended his philosophy to those he employed, be they humans or animals. But the sentiment is one that many modern-day entrepreneurs say they rely on.
Elon Musk regularly addresses Tesla customers' issues over Twitter, thanks them and asks for their input. The tech CEO has even tweeted at a single, frustrated customer on a Friday night, showing his commitment to customer service.
Robert Wang, inventor of the current kitchen craze Instant Pot, recently revealed how he shows his gratitude toward customers. In all official branding photos for the product, the timer reads 5:20, which when spoken out loud, sounds like "I love you" in Mandarin, his native language, according to the New York Times.
"Customers are most important for us. As inventors, we feel good if our invention has created value for people. So we put 5:20 on each cooker," Wang told CNBC Make It.
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