I've been told that when someone does that (just disconnect) it's even better than a resign, you take their dignity as well as the game!!
Some folks disconnect when they are losing instead of resigning
It is the same thing as resigning, except that the player did not do a fomal resignation and that seems rather impolite as well as odd since the guy has in fact given up.
In some cases it happens that a player looks at the position trying to find a rescue then put the game to rest for while, then take another look to try figure out a rescue, then put it to rest again, then later on giving it another look and so on without finding any good answer. Then suddenly the time ran out. But that is a special situation since the guy did not actually just disconnect from the game.
Those who just disconnects have obviously given up, so pushing the resignation button would simply make sense.

I agree. I think it´s cowardly and very impolite for the other player who has to sit there for a few minutes before the game ends with the "game abandoned" sign. I think some players are silly enough to think that they will not lose points if they disconnect instead of resigning but it´s not true.

But, sometimes it was the server has been unstable and disconnect the players. It happened to me one time, and another time was my opponent. According to my opponent he was not trying to disconnect, and his position was winning. So, there was no reason for him to disconnect and reconnect. Some players who live in a remote areas in India and Africa also have unstable connection with the internet.

It happened to me a few times that i disconnected. I played and still playing from a fragile wifi connection. Sometimes when i am winning still disconnected. Very often my opponentes disconnect too I dont hink anybody disconnect because anger or somethin like that. Sure it happened to me that my opponent rage quit :D.....most of the time if i can i am resign to save time....the most annoying thing in my opinion ...when somebody not disconnect just wait for te end of the game....i think it is rude

It's said Curt von Bardeleben once just got up and leave the room instead of resigning during a game against Steinitz...

4 minutes to go, 1 move from checkmate and feyziyev disconnects. How are these players allowed to stay in the Chess.com community?
seems a little rude