What's stack rank mean for a work item in Team Foundation Server 2010? Is it a user characteristic of some kind?
Answer
In most cases priority and stack rank are aligned i.e. on average higher priority items will have lower/earlier rank... BUT
Stack Rank is not priority. It is just the order in which your team will work i.e. Rank 1 is the item on which your team will work first, Rank 2 is the second and so on...
so when does a lower priority item get an earlier/lower rank..
Example 1 Let's say you choose 3 bugs to fix in the current iteration.. 1 is high priority and 2 are medium priority.. but, lets assume, fixing one of the medium priority bug means regression testing.. so you will like to fix it at the earliest so that regression effects are visible at the earliest..
Example 2 a higher priority item needs more info before you can start working on it.. so you will keep its priority high but will move some lower priority item to earlier rank so that your team can continue working...