Electrolytics are generally more prone to failures than other types of
capacitors. Not to say that one has to be paranoid about them!

They:
1/ can develop high series resistance as they dry out
2/ can exhibit more leakage over time (both electrical and physical)
3/ can lose their effectiveness over time (mostly as they dry out)
4/ can explode due to internal gassing
5/ can damage circuit boards when they physically leak their electrolytes
6/ are mostly intolerant of reverse polarity
7/ are absolutely the best choice in many designs