Iterations are usually limited when the waterfall model is used, because (a) Iterations can be costly and and involve significant rework (b) Iterations add little value when the product is almost...

Iterations are usually limited when the waterfall model is used, because (a) Iterations can be costly and and involve significant rework (b) Iterations add little value when the product is almost finished (c) Iterations require user feedback and the users are not always known (d) Iterations require full agreement by the users and it is hard to get consensus