A test environment is not always available or suitable, but it creates a safe space for learners to make mistakes. A test environment should allow students to make all the possible mistakes in this safe environment and learn from the consequences. This learning experience is common in some fields, like developing code, but can be applied more broadly to other disciplines. From administering doses of pharmaceuticals to identifying problems in accounting documents to working with problematic data sets. Test environments develop an understanding of the consequences of their actions and decisions and provide a way to experience the consequences and confront them through their mistakes. Getting something wrong is necessary for learning, but it can also be demoralising. It's vital to enable students to uncover their mistakes, learn where they went wrong and try again.