Couple of things I've done. One is build refactoring into the estimate for the improvements, especially since if you did take two months to refactor and then ad

Couple of things I've done. One is build refactoring into the estimate for the improvements, especially since if you did take two months to refactor and then added improvements, you might have to refactor yet again. Another thing I do is reserve X% of sprint stories for maintenance work such as refactoring so some improvements do get made. I don't think you ever fully pay down tech debt, you just have to do as much as you can given other constraints.