Jörgen Elfving is a former lieutenant colonel with a background in military intelligence. He has written a book on Russian military tactics and continuously follows developments on the battlefield.
He says that one should not underestimate the difficulties of breaking through the Russian defense lines. The linear defense makes it more difficult to make up for lost terrain and face an attacker, Elfving says. He speculates that simplicity alone has made the decision to use this method to defend the occupied territories of Ukraine. He does not know why the Russians have chosen this method, they have not given any explanation.