The Re:view extension for Chrome allows you to easily view and test your WordPress site for mobile. Verifying that your website responds to a mobile or tablet format in a user friendly way ensures that users have a good experience navigating your site regardless of what device they are using. Responsive websites also benefit those who may be using assistive technology such as a screenreader to view your site.
If your content does not function as intended, a reorganization of the page or content is probably in order. You may also encounter things like text that takes a long time to scroll through when viewing on a mobile device. Anticipating how your audience is interacting with your website (e.g. mobile device or tablet) can prompt you to organize and design your content with your audience in mind.