While Scrum allows some room for customization, there are some elements that teams should not change or omit, as they are essential for Scrum to work effectively and deliver value. For example, it is important to uphold the Scrum values of commitment, courage, focus, openness, and respect - which help teams build trust, transparency, and collaboration. Additionally, the Scrum principles of empiricism, self-organization, collaboration, time-boxing, and value-driven delivery should be followed in order to inspect and adapt their work based on feedback and data. Teams should also not skip or alter the Scrum events such as the sprint planning, the daily scrum, the sprint review, and the sprint retrospective - which help create transparency, alignment, and learning. Finally, teams should not ignore or modify the Scrum artifacts like the product backlog, the sprint backlog, and the product increment - which help create visibility, accountability, and quality for their work.