Complementing Klaus comments:
Electrolytic capacitors have a liquid electrolyte. That liquid slowly but surely escapes thru the bottom seal.
This can take many, many years if the capacitor is not being used.
However....temperature causes liquids to expand, even to boil. The increased pressure will significantly increase the electrolyte loss.
High ripple currents cause internal self heating. If additionally you have a high ambient temeprature, the electrolyte will be lost very quickly.
Since you are posting in the power electronics forum, I assume that you have an interest in building a power supply.
If so, I'm going to give you the best advice: Avoid the 85-C rated capacitors. Always use 105-C or 125-C rated capacitors. They cost a little more, but will last significantly longer.