To be sure there is satisfaction in successfully assembling a model; and some understanding to be gained in seeing how the flat parts go together to make a 3-D form. Yet after a few successful attempts, one begins to think about how a model could be changed: What if you could create something that might not have ever existed, such as a three-headed raptor with wings? What if you could design your own cabinet or table, instead of accepting the stuffy conventional models that come in the box? In short, with a store-bought model you are limited to.