How agile scrum overcomes the drawbacks of waterfall?

Agile scrum is an iterative and incremental software development model. This means that they are building smaller blocks of software and involve stakeholders for earlier feedbacks/reviews. This means that they can reduce the delivery time as well as ensure a high customer satisfaction due to higher software quality. There is no lengthy documentation process which adds to quicker delivery.
If there are any changes to the requirements especially during the testing phase, it will be quicker and cheaper to implement the change in agile scrum. The changes can be easily incorporated into the next sprint or the current sprint if it is a high priority item.
The development team (scrum) is more collaborative and because they are involved from the planning stage, the team is more comfortable with the estimation of the tasks that they are working on, thus increasing the likelihood of delivering the software on time compared to waterfall model. This is because the team was not involved in the planning and estimation phase and some of the risks were not thought of by the Dev and QA lead at the time.