I'm playing Red right now, and in Gen 1 I've noticed that sometimes when you use a stat move or something like that it sometimes says "It didn't affect the foe's (Pokemon name)" or something like that. Why is that?
The only reason I could see why this would happen is the following:
EDIT: Speed Freak had the same problem here and some answered saying it may of been a glitch.
If its none of these then i'm not sure :/