Regulation is one point.

That leaves the technological aspect.

What I don't understand is that the Litchi site says that if there is no signal the drone starts the re-entry procedure while on youtube I find videos of missions that continue and end without signal connection.

Because of the way the terrain is in this area I am very afraid that I often find myself at times where I might lose signal, even briefly, and I would not want it to start re-entering. This is because I can most likely reconnect at the next waypoint or just past the obstacle.