The first chapter of the project is simulation and software development. It is highly recommended that you simulate your project beforehand to avoid mistakes or problems in later stages. Furthermore, simulations can provide an excellent testing environment to try different scenarios for your solution.
Depending on your project, you may be interested in having a simulation environment where you can test your solution. In other cases, that's the only option you have since you need to wait for the supplies or works in different groups. Concerning that, simulations can provide an excellent testing bench where you can try the best and worst scenario for your solution, saving you time and money.