Primavera has three Scheduling Options to choose from when you are scheduling your project. Retained Logic is the default scheduling option. When you are building a Baseline, the default option works fine. But things change when you start updating your project, activities start getting delayed and do not get executed as planned. You then have to make a decision on whether you want to continue using Retained logic or choose Progress Override or Actual Dates as your Scheduling Option. A lot has been discussed over the internet forums on which option is the best for a project and Retained Logic has won with an overwhelming majority. But I have a different opinion.