Does your website display correctly on some, most or all the different size devices that will browse your websites these days? How about on a mobile device (2"-4" screen / 300 - 600px ), tablet (6" - 8" / screen 700px - 1000px), desktop monitor ( 17" - 27" and up / 800px - 2000px and larger)?
Is your website formatted and optimized for each display? Does everything display correctly? Especially on mobile but on all sizes is it functional? Can you navigation to all or for that matter any of your interior pages?