Yeah, psycho destroyers... especially in SH2.
But that was early in the game (before the invasion of Norway), I was green as sea weed and wet behind the ears at the time, having only had SH1 as previous Sub sim experience, so my perception at the time was that some of the destroyers were just plain homicidal psychopaths the moment they detected me or were otherwise alerted to my presence (that and watching on external camera as depth charges landed ON the conning tower...)
It was either dumb luck, or some of those destoyers in SH2 had gun sights underwater with the accuracy they dropped with...
I didn't have that kind of trouble with SH3, at not least in terms of deadly depth charge accuracy, but perhaps in terms of persistance...