Being honest works because it:
I hope no one is straight up lying to people in their marketing or internal communications.
But then again...
"Honest—sincere, passionate, real, authentic, open, sharing, and understanding that the buyer is in control."*
Honest is a result of your organization's culture. Trust is the foundation of a relationship and honesty is a first requirement for trust.
Is your culture transparent with information or do your senior people hoard it and keep everyone in the dark? My experience tells me that companies that withhold information from their people are very likely to withhold valuable information and expertise from buyers. Transparency internally leads to transparency externally.
Build trust internally to show you are worthy of it from your customers. If your employees are trusted they will show that part of your culture to your prospects and customers. If they fear transparency then they will fear being open, honest, candid, and human with your prospects and customers. They become closed off, reliant on scripted answers, and find comfort in spouting the company line. Buyers see/hear/smell this attitude a mile away and run to your competition - which as you know in this age of the modern buyer they can find in a click of the mouse or a phrase spoken into their phone.
Honest communications starts with transparency internally and extend to every relationship your company has with employees, partners, prospects, and customers.
"Consumers can handle the truth, and the information they do want to know they want delivered in a clear, forthright, trustworthy, and easy-to-find way that conveys some sense of vulnerability and openness. This is a crucial area because I think honest clarity is the currency of trust in the digital age."
—Food Marketing Institute President and CEO Leslie G. Sarasin
*Inbound Organization, Wiley 2018