I was reviewing a code and came across something as

 
public doSomeStuff(String shortMonthName){
 if(shortMonthName.equlaIgnoreCase("jan")){
 //do something}
}

.
In this code client passes a month name based on which some logic is executed.

At first it might look as whats wrong? hmm ..what if in future multilingual support is introduced -the month names will be localized and the client supplies equivalant of “jan” in a language other than english –it will simply fail.This is a very simplistic use case, but hope I make my point

Never use data which can be localized as part of a business logic