Originally crucification took a long time and was extremely painful. Nails through hands and feet. You can’t breath while hanging well enough so you have to push yourself up by “pulling” on the nails through your hands while “pushing down” on the nails through your feet to let the lungs expand so you can breath. As the pain/shock takes over, you begin to suffocate because you lack the strength etc. Grisly. It’s actually a relief that they beheaded that person first - more merciful.
I read about that during my roman studies and yeah, better to have been beheaded first before all that, it was a final mercy they gave him.
I believe the nails were used in special cases. Most of the the time they were just strapped up on the cross. The pressure of trying to support yourself while your arms are splayed eventually leads to a collapsed lung.
The methods of torture in the past were particularly grim. I have often wondered how the methods spread from one region to another. How does that conversation start:
“You know how those guys strapped people to the cross? You know what would be cool? Nailing spikes through their hands and their wrists. I bet that would sting.....”