"UPDATED" glock 19

I was wondering if anyone here can shed some light on this for me;

I bought a used glock 19 in 1993. I noticed the other day that on the side of the box, was the bold printed word, "UPDATED".

Does this mean the glock was once a lemon and returned to glock to get updated? Or was this firearm at one point in time recalled, but before leaving the factory, "UPDATED"?

The guns fired flawlessly from day one. I was just curious.

Thanks,

Jimmy