How will most people see my website?
Most people these days surf the web on a mobile device. Which is good, because that means they’re more likely to have been redirected through a social page of yours. However, on a mobile device, many websites crumble under the re-sizing and formatting, making the site unintelligible and messy. With a more responsive layout, your website will look outstanding compared to the rest. Responsive means that the code for the website is mobile friendly, it responds to the new format that it is put into and conforms to the new boundaries.
With a responsive online store, people can buy from you instantly whenever they want. With a responsive website, people will be able to view your content with ease wherever they are.
Accessibility = Traffic.