According to the developers, earlier the chances of victory were increased for those who were lucky to be inside the safe zone. Also, players, as a rule, fought not with enemies, but with the blue zone, trying to hide throughout the match. The authors believe that both of these problems can be solved by showing the players where a new circle will appear.
That is why the inner blue zone not only appears in the safe zone from the very beginning of the game and remains until the penultimate phase, but also corresponds to the size and location of the next safe zone. However, players will not be able to sit out in the inner blue zone because they will receive damage.
While developers have conducted an open test of the inner blue zone in PUBG Labs, however, in the future, it may appear in the main game modes.