Agile Modeling Principles

Primary goal of the software team is to build software not create models.
Travel light- don't create more models than you need.
Strive to produce the simplest model that will describe the problem or the software.
Build models in a way that makes them amenable to change.
Be able to state an explicit purpose for each model that is created.
Adapt the models you create to the system at hand.
Try to build useful models, forget about building perfect models.
Don't become dogmatic about model syntax. Successful communication is key.
If your instincts tell you a paper model isn't right you may have a reason to be concerned.
Get feedback as soon as you can.