Stupidity: Why on earth would the prisoners gang up on Hancock in the prison yard and threaten him with violence? They know who he is, and they know he is an invulnerable superhero and could take everyone of them down painfully with one hand. Even those who don't have personal experience of him would know from the media reports that he cannot be beaten by a human being. Don't tell me they think he is a reformed character or that he has somehow been 'weakened' by his imprisonment - they continue attacking him AFTER he has violently punished two, brutally humiliating two of them for merely threatening him - and they hurt themselves hitting him even when he just stood still and took it. Basic prison mentality - do not attack an opponent that you cannot beat. Losing a fight means losing status, losing face, and in a hellhole prison like the one in which Hancock is incarcerated, that can be - and often is - fatal.
Stupidity: Someone with the Punisher's tactical knowledge would not hang upside down from a chandelier to shoot in a 360-degree pattern at his targets. This would make him a sitting duck and it's only because of the movie tropes of Stormtrooper aim and cannon fodder henchmen that he isn't killed because of it.
Stupidity: Near the end, Sydney Wells and Paul Faulkner try to rescue a little 10-year-old girl who is trapped in the recreational vehicle. Sydney is banging on the door from the outside while the little girl is banging on the door from the inside. Paul then smashes out the door window, reaches inside and easily releases the door latch in one move. So, a 10-year-old girl was "trapped" because she couldn't simply open a door latch? Stupid.
Stupidity: At the end of the film, Abel had nothing to gain from lying about having a gun to the police officer. He had no way to prevent Chris and Lisa from presenting the informant's cell phone and exposing his involvement in the break-in and vandalism of the couple's house. Additionally, testing from the shots fired in the house and the car would prove that there were two different guns involved. As a long time police officer, Abel should have known that giving up the gun would have been the easier way out instead of lying about it.
Stupidity: When she leaves him at home with a sandwich she says people will come check on him. When she gets home and he's not there, she doesn't go and ask those people where he is.
Suggested correction: It wasn't so much as them believing they could beat him. But several factors here. The invincible superhero is suddenly in prison and not breaking out. It is reasonable to believe that a lot of inmates would think that perhaps he has been weakened and thus vulnerable and see this as opportunity for revenge. Even if that's not the case, basic prison mentality is to prove dominance and show no weakness. Attacking Hancock would demonstrate to the other prisoners that they did not have fear and were tough, even if they couldn't win as a way of proving themselves. Not only this, but the type of people in a prison tend to not be the most forward thinking type.
Quantom X ★
This correction is just plain wrong. Do you think Mike Tyson was ever attacked during his incarceration? Not a chance. I was in the Melbourne Remand Centre when a karate expert - he came third in the world championships - joined us after being banged up on his sixth dui charge. He was "ghosted" - that's an actual thing in prison - treated as if he wasn't even there. Not even the toughest of the tough would even acknowledge his presence.