A Retrospective means to look at the past events and define what went well and what can be improved. In product management, a retrospective is usually done after a launch to identify the bottlenecks and what is working for the team. The stuff which is working should be done more to increase the productivity of the team. The stuff which is blocking and can improved should be taken care off to avoid any harmful practices or bottlenecks which can affect the delivery of the product.