SAP Fiori v/s SAP UI5

Hi All,

     I am asking this question in layman terms. Although technically what i know is that SAP Fiori uses SAP UI5 Framework for its compilation and working but having said that, since we already have applications accomplishing client requirements from SAP UI5 (with SAP ABAP and SAP Netweaver Gateway), what is the need of something like Fiori. I mean there has to be something that must have struck SAP that lacks in UI5 that they thought of launching something similar to it with a different brand name. I am looking for non technical feedback as to why one will choose to prefer SAP Fiori over SAP UI5 and vice versa. If anyone can throw some light on the same, it would be really helpful.

                                                                                                                                  Thanks,

                                                                                                                             Vaibhav Deorukhkar