RPO is extent of acceptable data loss. For example, if RPO is 2 hours, then organization can afford to loss at the most data captured during last 2 hours. They need to design back-up strategy in such a way that back-up should be taken every 2 hours. Back-up is taken at 2.00 PM, 4.00 PM, 6.00 PM and so on. In this case, if data is corrupted at 5.59 then back-up data upto 4.00 will be available with the organisation. Hence data loss will not be more than 2 hours.