Email is important for banking industries for several reasons. It allows for seamless communication with customers, easy access to data through cloud services, and the ability to manage customer data as needed. Email also enables personalized services through customized content, strategic lead generation by building quality email lists, and instant delivery of engaging content in real-time. Additionally, email services are affordable with low investment and high returns, secure through integrated APIs and SMTP servers, and the preferred method of communication for most customers.