Believing it is a process only change, and missing the mindset and cultural change needed to be successful. Far too often leadership state the equivalent of “go do that agile/scrum thing and give me what i ask for faster” without realizing it requires extensive, enterprise wide changes. They often miss that the secret sauce to true agility involves moving away from requirements and towards defining opportunities and issues to resolve. Moving from command and control and towards creating environment and context to influence outcomes. Realizing that product developers are not ‘resources’ (a resources is the laptop sitting on your desk), but instead are people with goals, ambitions, and have lots to contribute to the solution.
In general, Scrum implemented at the team level without the agile mindset at the leadership level will never deliver it’s full potential.