Top 5 Reasons to Use Responsive Website Design. The introduction of smart devices and their ease of availability have shifted the use of the internet, from desktop PCs to hand-held smart devices. A research suggests that the year 2015 will witness internet usage on mobile devices to match the usage on desktops. This means that all businesses should ensure that their websites are compatible with these devices. Being compatible in this way means that the website automatically detects the device, while it is being viewed, and adapts to the screen size for easy viewing. This adaptability feature is known as Responsive Website Design.