Why does everybody suggest surrendering so often? A common term / conversation I hear is :

"surr at 20"



And then a heated conversation starts up.

An example of how people think they instantly lost, is when I was playing a good AP Teemo round. It was 3 v 5, i was handling bot, Diana was in mid, and Ashe was on top. We explained to the other team how it was 3 v 5 and they said they'd go easy until level 6. We reached level 6, and they sent 3 people to bottom because of me. A little later, we spiked up a team fight in mid. I killed Garen with a Blinding Dart, GP with auto attacks, Pantheon with a Blinding Dart, and I chased Draven into a shroom for the quadra, the only reason there wasn't a penta or an ace is because their Rengar was at base. Five seconds later they surrendered. I understand that we could've got a good push but it was at the 22 minute mark and we had no turrets on them, but they had turrets on us.

So why is it people surrender? I'm curious to know, and I think seeing other users opinions could maybe change the way people think when they see or start up that surrender vote.