Justification

More than one exit point indicates a forced break in control flow and, like any break in control flow, leads to code which is more difficult to read and maintain.

Example 1

if (i > 10)
{
   return (i - 10); /* WRONG */
}
else
{
   return (i); /* WRONG */
}

Example 2

var result = 0;

...

if (i > 10)
{
   result = i - 10;
}
else
{
   result = i;
}

return result; /* RIGHT */

Exception

Multiple returns are allowed in case of simple (failing) tests at the beginning of a function. This is called the fail-fast pattern.

Note

Do not confuse an exit function call with a "return" statement: a "return" statement is to return to its caller, where an exit statement is to terminate the program execution.