Final answer:
Firms in the marketing era adopted a market-oriented approach, focusing on what customers desire and creating products that align with those needs, driving product differentiation and corporate personalities.
Step-by-step explanation:
In the marketing era of business development, firms adopted a market-oriented approach, which means they find out what customers want and need and then design products to meet those needs. This concept is rooted in the idea of selling not just products but the hopes and dreams associated with them, as discussed at the 1923 convention of marketers. With the advent of consumer culture, the push for product differentiation and corporate personalities grew stronger, as businesses strived to make consumers believe that their products were unique and essential for achieving a certain lifestyle. The evolution of markets has been heavily influenced by the rise of technology and globalization, making competition more intense and expanding consumer choices beyond local retailers to global suppliers.