Microsoft is really careful with new software territories. Like a giant who is too strong they try not to annoy the little customers in the china shop. Like other companies, Microsoft is afraid of regulations and of course faces constant litigation.
Sometimes, Microsoft executives decide that new products should not be indirect competition with other successful products. For example, the first Windows CE devices were really expensive high end ones and for a while, not really that succesful compared with Palm's offerings. But things moved on and suddenly Microsoft had the better product. Microsoft can afford to lose money on products, patiently waiting for the right time to strike.
DPM is such a product, favoring backup to disk drives over the ancient yet still popular tape. Now it is at version two and is still considered a really high end product though Microsoft does want to broaden the audience a bit. will things move on again and everyone will want a version of DPM instead of Arcserver and BackupExec?
Read more here: