When Something Is Vagaries?

A vagary is an unexpected and unpredictable change, and the word is usually used in the plural. You might know from experience that the vagaries of winter weather make planning a vacation in February a risky proposition.

What does the word vagaries means?

: an erratic, unpredictable, or extravagant manifestation, action, or notion.

What are the vagaries of life?

One dictionary reference I found defines it as “an unexpected and inexplicable change in a situation or in someone's behavior.”Other words associated with it include change, fluctuation, variation, quirk, peculiarity, oddity … caprice, foible, and so on.