Walk down a typical suburban street and you might come across a sign like this. It’s usually cluttered, with awkward formatting and mismatched font sizes. Here’s one I spotted in Houston. Source One line really caught my attention. It says, “Window cleaning in progress.” I love this sign because it highlights something most marketers overlook. K&C Window Cleaning isn’t trying to win you over with flashy taglines or loud, aggressive claims. Their approach is much more understated—and that subtlety actually makes the message more powerful. Advertising is about influence, but nobody enjoys feeling like they’re being sold to. Instead, this sign taps into psychology, prompting people to think, “Other people are getting their windows cleaned, maybe I should too.” The idea feels natural, not pushy. Table of Contents We follow the actions of others We don’t like to feel pressured We follow the actions of others Back in 2008, renowned researcher Robert Cialdini conducted a famous study. Over 80 days in a mid-range hotel in the American Southwest, three researchers ran experiments in 190 rooms. Their aim was to get guests to reuse their towels. In each room, they tested different signs with more than 1,058 visitors. One version used a typical environmental appeal: “Help save the environment.” When asked, guests said this was the message they believed would influence them most. But the researchers also tried a different line: “Most guests reuse their towels.” The outcome was unexpected. The environmental message led to a 35% reuse rate, while the suggestion that the…