This is really pretty straight forward. The most valuable thing on a system is the data. This is your photos, videos, spreadsheets, documents and the like.
Hardware can be replaced or repaired. Software can be re-installed. Your data is personally unique to you, your family or your business and a value can not be placed on this information.
Roughly ninety percent of the time when we see a catastophic system failure, we have the ablility to retain your data. That leaves ten percent. Of that ten percent, about eight to nine percent can be recoverd by other companies that we have partnerships with. However those services can be very expensive. That remaining one or two percent of complete loss is a rarity. So we always recommend having your data backed up in one if not two places.