

The word “go” has lots of meanings besides physically moving to a place. It also means to change state (“the milk went bad”, “he’ll go crazy when he finds out”) and to indicate immediate future tense (“I’m going to read this book now”). Not to mention some other less relevant uses.
Were perfect. The conditions on earth back when life first appeared were very very different than they are now.
As for how many times it may have happened, there’s no way to know, only that it happened at least once (edit: unless it happened elsewhere and came here somehow).