Aside from outright "it popped and oozed all over the place" failure, you've got drift in specs-- the original design expected 100 +/- 10uF, and you're now at 6

Aside from outright "it popped and oozed all over the place" failure, you've got drift in specs-- the original design expected 100 +/- 10uF, and you're now at 60 or 125uF, with a different equivalent-series-resistance and leakage than the part had when new. In a lot of cases, this won't directly cause explosion, but it might make for a noisier signal down the line. I've replaced the electrolytic caps in two different stereo recievers and one amplifier, all from the 1977-1980 era. Only one of the three had noticable difference in sound quality, but it was the one that had clearly been abused over the years (failing power switch that arced and sputtered, absolutely filthy and blown bulbs when I got it)