In my personal experience, the biggest problem I had with UML is tool support. Most modelling tools are terrible and/or very expensive. Modelling is very tool

In my personal experience, the biggest problem I had with UML is tool support. Most modelling tools are terrible and/or very expensive. Modelling is very tool dependent, without a good tool that help you view, edit, print and manage your models; you will just quit it. A mature, FOSS tool, can take UML a long way!