Debugging most Validation Rules can go two ways: Hours of debugging with trial and error OR a 15 minute read like a well written business requirement.
The cleanliness and formatting of the Validation Rule defines the difference.
If you own a Salesforce Platform and are NOT investing in clean, well formatted and designed validation rules, you are wasting money.
But be aware, you have to make them clever before the bug is reported to make sure you properly test and validate the new format in the wild. Hunting a bug AND refactoring a Validation Rule doesn't go well together.
My recommendation: Start with your global settings (Bypass, Custom Permissions, Profiles...) and get more and more detailed the lower you go.
And always optimize readability over cleverness. Don't worry about repeating yourself if it makes reading easier.
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