All databases I am aware of work based on CRUD: Create, Read, Update, Delete. Drupal always wanted to implement all of them nicely and now we have a nice Read in Drupal 7 with entity loading. Delete API has a very long and very sad history which I won't get into but we tried to introduce Delete API to make undo possible. As teached by many excellent usability books, confirm forms are wrong, they become habitual and are just a nuisance instead of protecting you from mistakes. The computer should just do what its operator says and make it possible to revert easily.