Fundamental to user engagement
Every user who visits your site needs to be visually entertained and intrigued or they wont stay much longer then a second.
“Once your page loads, users form an opinion in .05 seconds.” –
If we were to take the desktop version of your website and merely shrink the same design to fit on a phone it would hardly be legible, much less visually pleasing. This is where responsive website development comes into play. With a properly developed website the content will adjust based on the width of the device it is being displayed on.
Vital for SEO (Search Engine Optimization)
Mobile friendliness now plays a part in your search engine optimization strategy. As of April 21st, 2015, Google began penalizing websites that were not mobile friendly on the page ranks. These days, if someone on a tablet or mobile phone does a google search, only mobile friendly websites will filter into the search results. As less users get to your website via mobile devices your website will also incur a loss of desktop visitors as overall traffic decline also creates a negative effect on site weight in general.