Flexibility: There is no expectation on certain values being present in lookup tables. The model can be easily adjusted for any values in it. Also, hierarchical tables ensure flexible custom classifications.
Client data protection: Personal Identification Information is stored in dedicated tables which allows encryption. PII data is any data that could potentially be used to identify a particular person. Examples include a full name, Social Security number, National Insurance number, driver's license number, bank account number, passport number, and email address.
Normalization: Data integrity and performance.