"Takedowns against dazed enemies usually take away a single enemy corpus completely, which can lead to an insta-kill.
However, some enemies like the "Nexus Engineer" or "Soldat" have 2 or more corpuses.

Knowing this, you can "save" your takedown until you have fully taken away their first corpus. This way, you will be able to kill without seeing them standing back up.

It's better to do this if you are not being surrounded."