easy to change / destined to change

Buy it while it is cheap. The price of these is prone to change daily. (=likely)

Prone to change, it is something that has got possibility or weakness or even eagerness to change. If a culture is prone to change, it means this culture is weak or eager among the people who are from this culture and it has got possibility to change by the effects of other cultures.

Prone to change, in general, means something that is sensitive or vulnerable to change. So if you think about it with culture it would mean that a culture could be vulnerable to change or likely to change. Hope that helps!