The environment in which the story takes place can also be a reason. For instance, if the fanfiction is set in a post - apocalyptic Gotham, Batman has to deal with harsher conditions, more desperate criminals, and less resources. All of these can contribute to him getting hurt more easily as he tries to maintain order and fight crime.
A common reason is battles. Sasuke is often involved in intense combat situations in fanfiction, whether it's against old foes with new powers or entirely new enemies. His determination to prove himself or protect something often leads him to take risks that result in getting hurt.
Perhaps in the fanfiction, Batman gets hurt during a high - speed chase. He might be driving the Batmobile and something goes wrong. Maybe his vehicle is sabotaged, or he takes a risky maneuver to catch the criminals and crashes, resulting in him getting injured.
Equipment failure can be a factor. In fanfiction, his web - shooters could malfunction. Maybe they run out of web fluid at a crucial moment during a fight, leaving him without his main means of movement and defense. As a result, he's more exposed to attacks from villains and gets hurt.
Another reason could be external threats that target Starfire specifically while Robin is trying to protect her but fails in some way. For example, a powerful villain might know of Starfire's weaknesses and use them against her, and Robin's attempts to counter the villain's attacks might not be enough in time, thus she gets hurt.
In some fanfiction, Batman might get hurt while investigating a dangerous criminal organization. For example, he could be caught in a trap set by the Penguin. The trap could be filled with sharp objects or poisonous gas, which would injure him. This would then lead to him having to rely on his wits and the help of his allies, like Alfred or Robin, to get out of the situation and recover. It also shows how his detective skills are put to the test not just in solving crimes but also in surviving life - threatening situations.
He could be exploring an old, abandoned building and fall through a rotten floorboard.
One possible reason could be a misunderstanding during a mission. Maybe Erza's actions were misinterpreted by Natsu, leading to him getting hurt, either physically or emotionally.
One reason could be that he was being a bit too adventurous. He might have tried to climb a tree that was too high or unstable for him. As he reached for a higher branch, he lost his balance and fell, getting hurt in the process. Also, bad weather conditions can play a role. If it had rained recently and the ground was slippery, Chris could have slipped and fallen while walking in the park.
One common reason is his inexperience. He's still a young superhero, and in the chaos of the Civil War situation, his lack of experience can lead to mistakes. Another reason could be his loyalty. He might put himself in harm's way to protect someone he cares about, like Tony or Steve, without fully considering the risks.
In a fanfiction like this, Batman could get hurt while on a solo mission that was supposed to be a simple reconnaissance for the Justice League. However, he stumbles upon a hidden lair full of traps. One of the traps could seriously wound him, like a large spike that pierces his side. This would then lead to a race against time as the other Justice League members try to find him before his condition worsens.