Scope minimization helps to capture common programming errors, improves code readability by tying together the declaration and actual use of a variable and eases maintainability since because unused variables are easily caught and removed.
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This noncompliant example shows a variable that is declared outside the for loop. This can harm reusability since as the loop index i will change after the for statement. Consider for instance, if the case when this code snippet is copy pasted with the intent of using a different index j but the statement mistakenly still iterates over index i. Since As i is still in scope, this will lead to a rather obtuse outcome.
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Additionally, methods should be designed for only one operation if possible. This simplicity avoids variables from existing in overlapping scopes and prevents errors.
Risk Assessment
Using a larger scope than necessary results in less reliable code.
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