I think the main and most important difference is ‘Project Management’, the way its done in traditional models is drastically opposite to the one in Scrum. In Scrum, the scrum team in a way is responsible for handling and taking care of ‘Project Management’. Following are the reasons that I can quote in favor of it:
- Sizing(Estimation): In SCRUM it is done by the team along with the product owner and SCRUM Master during the SPRINT planning meeting in contrast with traditional models where Estimation is done by managers.
- Communication Plan: In SCRUM, Transparency and timely communication is the key to success and these are implemented through daily stand-up meetings and in other rituals of scrum (Sprint Planning, Scrum Of Scrums, Sprint review ).But in older software development models the communication plan is created but actual implementation is not so powerful.
Customer Acceptance: Sprint review/Sprint Demo meeting is an important ritual where product is showcased to customer and stakeholders, and is being accepted, instead of waiting for long time (months/years) in older models to get acceptance. It is the scrum team along with Product Owner that defines acceptance criteria during Sprint planning. In contrary, Dev. team was not involved in defining the same in Older models.
Retrospection(Lessons learnt): It helps team to self retrospect at end of sprint and then plans for improving the areas identified for improvement.In traditional models, its done at the end of project, which is not fruitful.
I hope it will help you in improving the processes and outcomes of your projects while migrating to Scrum.