Snakes aren't very "social" pets & greatly rely on instincts, but I believe their previous handling (along with whatever genetic predispositions they may have) can
greatly influence how they react to future handling by new owners. Some snakes are more inclined to bite, but their early owners can make that worse or better,
so when you get a 2nd hand snake, that's yet another "risk". BPs are assumed to be mellow (about handling), but some just aren't so good at this. Just like any
other creature, including humans, it's both "nature" & "nurture", & sometimes there's only so much you can do to improve a "grumpy" snake. For sure, that's yet
another reason some snakes are sold (or given away- as was the case with a BCI I had for many years- I got her as a yearling & very prolific biter). It's one thing
if you welcome the challenge...quite another if it's not anticipated.