i'm not sure if other people have the same tendencies as me but i normally just passively feel attraction if i see anyone, it doesn't take a conscious effort
i don't want to sound dismissive by saying this, but have you considered that maybe that just seems standard to you because you're bi? people think in terms of their own experiences, and if you've always been bi, it would make sense that you'd have that expectation. not trying to be contentious or anything
I thought about that, and maybe that's the case, but I've never believed that orientation was a concrete thing, and that it's the same way for everyone. The reason I believe that is because it's easier to let people state their orientation, and then just have
that be their orientation, because what you identify as is your choice as a person. I believe the same for gender as well, and any other identity-related social construct, up to and including one's name.