These are caused when data structures contain data structure, and there is a need to run concentric loops, on them.
e.g.
for( int i = 0; i < some_integer; i++ ) {
if( i == PRESET ) {
for( int j = 0; j < some_integer; j++ ) {
if( j == PRESET ) {
for( int k = 0; k < some_integer; k++ ) {
//and so on.
}
}
}
}
}
The dazzling effects of the code are for everyone to "see".
I had come across this very pattern in my code. The root cause was that i was passing by value, and creating unwanted duplicates.
I changed everything to pointers and there was just 1 for loop and a condition check. Which was pretty cool.
So the next time you see the "arrow code", be pretty sure there is some unwanted checks going on.