likely to change
fickle - erratic
A person who is ‘fickle’ frequently changes their mind about people or things, so it is hard to ever gauge their true loyalties, opinions, or affections. The term can also be used with regards to weather conditions that may change suddenly and without warning.
Fans are so fickle these days. They will cheer you one week and boo you the next.
The weather can be so fickle here, which is why I often take an umbrella with me when I leave the house.
The designer said that his products adhere to a classical style, so they are not affected by the fickleness of passing fads.