ULIPs are not a pure insurance product, but combine the features of both Insurance and Investments. It is this flavor of investments that makes this product volatile and susceptible to market changes.
As a policy holder one can choose between the various ULIP plans that an Insurance company has and these typically vary according to the percentage split between debt & equity or the kind of sectors that the fund manager would typically invest in.

Given that the equity markets have a certain level of inherent uncertainty, it is obvious that many policy holders would want to re-think their fund selections - based on how the market has performed and what the projections look like.