“ONE MISTAKE CAN be a disaster,” says Antoine Ricardou, the 44-year-old founder of be-poles, a Paris-based branding studio. Ricardou has been putting the final touches on Le Barn, a new 71-room hotel on a horse farm 30 miles outside Paris in the Rambouillet Forest. The project, opening this spring, is a first for him and his 18-year-old company. In the past, when Ricardou has overseen the visual identity for hospitality projects—from the NoMad hotels in New York and Los Angeles, to the Four Seasons Surf Club in Miami and Les Roches Rouges on the Côte d’Azur—his design purview has been collateral: logos, do-not-disturb...