Use 'mutability' when discussing traits or qualities that can change, not physical objects. His opinions show a remarkable mutability depending on the audience.
Pro Tip 2/3
Neutral Tone
'Mutability' has a neutral connotation and doesn't imply whether change is good or bad. The mutability of fashion trends keeps the industry dynamic.
Pro Tip 3/3
Abstract Concepts
Best fits abstract concepts or systems rather than describing specific events. The mutability of the legal system allows it to evolve with society.