Wait, I lied (unintentionally). A couple of years ago I found that the last round in one of my mags for a little .25 cal pocket pistol I purchased back in '80 did a nose dive back into the mag every time I tried to fire with it. After certain efforts to remedy the problem with that mag, to no avail, I just chucked the turkey and was lucky enough to find a replacement at a gun show.
ASIDE from that one instance, my original post stands. (Embarrassment!)
(Never could understand why that mag and not any others. I could detect absolutely NO difference in any of them. In fact, the last time I tried to fire it at the range, I had to mark the defective one, being indisinguishable from the other two otherwise.)
GG