What might be a sign that a component is not sufficiently secured during assembly?

A sign that a component is not sufficiently secured during assembly is parts moving unexpectedly during operation. When components are properly secured, they should remain stable and fixed in their intended positions under operational conditions. If parts begin to move unintentionally, it indicates that they may not be adequately fastened or locked in place, which can lead to mechanical failures, misalignments, or even safety hazards. This movement creates a risk of damage not only to the components themselves but also to the overall integrity and functionality of the machinery or structure.

The other options, while they may appear positive, do not indicate proper securing of components. Zero vibrations might suggest a well-functioning assembly but does not provide any insight into the security of the components. Perfect alignment can occur with improperly secured components, leading to the misconception that everything is sound. Increased fuel efficiency is unrelated to the immediate physical security of components during assembly and is a performance metric that could be influenced by various factors outside of assembly quality.