SMS is an awful point of failure to inject into a protocol.  It is plain-text, monitored in many countries, and can be unreliable and expensive in emerging markets, and just no.<p>&quot;But users will forget&#x2F;loose their reset number!&quot; Maybe, maybe not. It&#x27;s a cultural thing. 
Really?  Can you cite anything here that indicates this is the case?<p>Users treat email access differently, seeing as how it&#x27;s bound to user identity, usually across dozens, if not hundreds of services.