Abstract is GIT for designers
Abstract will let you keep only one design file as so-called Source of Truth for your project. This means puting an end to endless complicated naming conventions for your -final, final1, final-for-real files and keeping track of every change in Branches inside of Abstract and then merging them into the one and only Master.
If you work in a bigger design team Abstract will help you to resolve conflicts while working on the same file, but different branches. It means no one can override your work by mistake. This is an ultimate solution and Holy Grail for design teams. In addition you can always go back and revert any change you made as a so-called commit.