My friend tried to start a business selling invisible products.

This joke cleverly plays on the double meaning of the word "overhead." In the world of business, "overhead" refers to all the ongoing expenses that keep a company running but aren't directly tied to producing a specific product or service. Think rent for office space, utility bills, or administrative salaries – these are all classic examples of overhead costs that every entrepreneur dreads, especially when starting out.

The humor comes from the literal interpretation when applied to "invisible products." If your products can't be seen, they don't take up any physical space. You wouldn't need a warehouse, display shelves, or even packaging, meaning there would literally be nothing "over your head" in terms of physical storage or display space. The irony is that while the friend's venture was a financial flop, it inadvertently solved one of the biggest headaches for any new business: keeping those indirect operating expenses to an absolute minimum. It's a silly, yet relatable, nod to the constant struggle of balancing costs and potential profit in the unpredictable world of startups.