I am supposed to drill earlier elements before adding new ones. Why do new ones keep coming up first?
The goal of SuperMemo is to provide a requested retention at minimum time. This goes against a widespread myth that the more you repeat, the better. When you first start learning with SuperMemo, you may be surprised that it waits a couple days before it starts drilling you on the newly added items. However, this is exactly the shortest path to your retention targets. It is no surprise that for many, SuperMemo seems counterintuitive at first.