That's entirely correct yeah, though often times the episode/unit director is different from the storyboarder, usually for bottleneck/scheduling reasons. Now that anime is mass produced there have become storyboard specialists that pump out very fast (but not very good) boards, and then they move on to the next production while the staff then assigns people to "process" the board.

In a more ideal scenario the storyboard artist and the episode director would be the same person because they can then better bring their vision to life. However in a commercially made anime there isn't much vision to begin with so speeding up the process is preferred.

There are also some people who just prefer drawing boards and not having to deal with later directing them, which is also valid. Ultimately, it's hard to say there is a best way to do this work since it varies depending on the individual people involved. But generally speaking, if you drew an ambitious board, the end result is better off if you direct it yourself.