Do you carry a BUG (Back-Up Gun)?
Do you practice with the BUG? By that I mean all the same skills you practice with your primary piece.
Do you practice drawing the BUG from where you carry it? Do you carry your BUG in an ankle holster? Do you practice drawing from it? Maybe you can’t at the range, but at least you can dry practice it at home. Can you draw from this location? Do you carry in a pocket holster? Can you get the gun in a good grip, out and on target in time? If not, reconsider your BUG carry location, or at least acknowledge to yourself the limits and constraints of the location and work within those bounds. Or perhaps you just may need more practice.
Do you practice transitioning from your main carry gun to your BUG? In the heat of a confrontation, transitioning to the BUG may involve dropping your carry gun on the ground and going for the BUG. If the S is H’ing TF, I don’t care what happens to my main gun (i.e. hits ground and breaks), but in practice I do care. I will practice this sort of transition over the bed, so when I drop I know my main gun is landing safely. This isn’t practicing so much about dropping my gun as it is drawing the BUG, but I also want to allow myself to know “yes it’s OK to just drop the gun… don’t waste time trying to find it a home like in the holster… the ground is a perfectly acceptable home when the fur is flying.”
If you carry a BUG, by definition it’s a second gun. That means the likely way you’ll get to it is because your first gun is no longer operational, thus transitions are something to practice. And don’t forget, practice going the other way too (BUG to primary) because sometimes it may go that way.