As a model maker, I can say that the more you do the better you get at doing it, whether it is your technique or that you just find better maybe faster ways of creating the models. Experience from trying various effects and methods help later when time constraints dictate so your models may well appear more 'polished'. I think every artist goes through the same process. Also when you are creating for an audience you become more self critical of your work so you want it to be better.