Scrum inserts artificial stopping points in the middle of the development lifecycle. The purpose of the sprints is to remind the team to go back and get feedback from customers at the end of each cycle and use that feedback as input to the next cycle.
few teams actually go talk to customers in-between sprints.
In Kanban, we create a task, and we’re always getting customer feedback. The
tasks done, we don’t have to break them down artificially, have meetings to talk about burndowns, or pretend we can estimate their duration using t-shirt sizes.