It's quite common expression (condolence?) we hear from others when we don't succeed in what we wanted or made an attempt toward. It's a kinda motivating gesture and to encourage the person by telling good try... you surely worked harder for it but...
Does the word try always mean the task/target/aim remained incomplete? In a dictionary, it is defined as..
try (v) - make an effort to accomplish something
But then, it simply leaves it halfway by telling 'make an effort'. What about the result?
By any means, may I greet someone with Good try when they succeed?