use strict; (and to a lesser extent,
use warnings;) helps find typos in variable names. Even experienced programmers make such errors. A common case is forgetting to rename an instance of a variable when cleaning up or refactoring code.
use strict; use warnings; catches many errors sooner than they would be caught otherwise, which makes it easier to find the root causes of the errors. The root cause might be the need for an error or validation check, and that can happen regardless or programmer skill.
What’s good about Perl warnings is that they are rarely spurious, so there’s next to no cost to using them.
Related reading: Why use