An ancient
Go proverb states "Do not play Go if you do not know the ladder". What the ladder is is essentially a deathtrap for a group of
stones. It is easy to recognize after you have played for a while but beginners often fall prey to it. One common example is shown below, the "X"s are black stones and the "O"s are the white ones, a period denotes a blank space, it is white's turn.
.............
....xx.......
...xo*.......
....x........
.............
An newbie would try to save their stone by playing at the "*". Lets see what happens next.
.............
....xx.......
...xoox......
....x*.......
.............
Black then responds by cutting off one of white's exits and putting the group in atari. Looks like white is in the same spot, it tries to play at the next asterisk to try and save its group now composed of two pieces.
.............
....xx.......
...xoox......
....xo*......
.....x.......
.............
....xx.......
...xoox......
....xoox.....
.....x*......
.............
....xx.......
...x..x......
....x..x......
.....x.x.....
I think you can see where this goes, white ends up with a rather substantial group captured and black is free to do a victory dance. Any situation like this will eventually hit a wall resulting in a capture for the opposing side. It is possible to setup a safety net that your group will run into that saves it, if you can do this you can quickly shred the poor defense that black has erected in trying to capture the ladder group.
The ladder is a potent weapon against newbies but once you begin to play intermediate and advanced games don't rely on it as an offensive weapon, most players will just accept the one piece loss and play somewhere more productive.