Can I ask, when you’re about to spike the ball, do you focus on the form of your hands and fingers or not? What do you think about when you’re about to spike the ball?
In my opinion , if you want to hit the ball hard you try to hit it with your wrist and contact the ball in the middle and if you want you can have an angle with it hitting with the side of your hands or adjusting your arms . I usually think of hitting the corners or the blockers hopefully dont block me . Hope it helps !
For me, you always need to anticipate what you want to do e.g. like how many blockers are in front of you, where do you want to put the ball (line or cross)
The simplest way to spike is to constantly look at the ball until contact. Directions and adjustment of power can be learned later. One mistake players do, like when spiking a ball to the stance(audience area), is once they've jumped already and waiting for the ball to the drop, at the last second, instead of looking at the ball, they drop their heads and looking at the opponents direction already and then... BAM!!!! Audience, thanking for that ball they caught.