I started writing Burp when I had become frustrated with the complexity and drawbacks of Bacula. I am in no way trying to denigrate the work of its authors - after all, it is also free software that the authors have very kindly provided. It also saved a lot of my wife's data when her laptop harddrive crashed one day (thank you, Bacula!). But here is a list of Bacula disadvantages I perceive that I hope to avoid with Burp.

• Complexity to configure - Bacula is just too complicated. It has four separate main components, each with their own configuration files.
• Complexity to code/debug - Kern Sibbald, the main author of Bacula admits that there is a distinct lack of community contribution to the code. I believe that this is partly due to the difficulty in understanding its complexity. They also have the need to continue to support, or provide continuity with the way things have gone before, which makes for slow development.
• Works badly with disk storage - Bacula's mentality is very highly geared towards tape usage and therefore it works poorly with disks.
• Stores the catalog separately to the backups - This causes a massive maintenance headache. For example, you now have to think about backups of your catalog. Additionally, changes to your configuration files might not take effect because some of the previous configuration gets written to the catalog, and then it is not easy to make the changes take effect. Furthermore, you end up needing to be a mysql or postgres database expert.
• Does not do delta differencing - Bacula backs up the whole file even if only a few bytes in it have changed.
• Relies far too heavily on clock accuracy - Bacula goes very badly wrong if your computer's clock somehow gets skewed. In fact, it relies so heavily on the clock and timestamps that it does not actually track which backup another was based on.
• Laptop backups are difficult to schedule.
• Cannot resume an interrupted backup.
• Retention configuration - it is just impossible to configure a sensible retention policy. Here is my explanation why, sent to the bacula-users mailing list.
• No Windows EFS support - EFS files are silently ignored.