Data backup continues to be a challenge for enterprises and especially small and mid-sized businesses, because it requires a multifaceted infrastructure of backup software, networks, servers, disk arrays and tape systems. Many firms have trouble completing backups in the allotted time, and a significant number fail or complete with errors. Often, companies don't protect machines at remote locations because of the hassle, so there are gaps in backup coverage. Because of issues like these, more and more frequently companies are turning to backup software as a service (SaaS) providers, which handle support and maintenance of a variety of applications over the internet without companies having to invest in any servers or install any software on-site.
Source: Computerworld, http://computerworld.com