Example 3. It reduces nesting.

I often invert the sense of a condition so that the shorter code block is the controlled block and early exit at the end of that block so that the following code needent be indented:

if (isTrue) {
   # long piece of convoluted code
} else {
   # short piece of simple code
}
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becomes:

if (isFalse) {
   # short piece of simple code
   # early exit (return or last)
}

# long piece of convoluted code
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