Video replay in soccer, as in all sports, sucks. This is true mostly for philosophical reasons, but also for logistical ones, too. Like when this Boavista fan inadvertently boned their own team by waving a huge flag that blocked the camera angle that probably would’ve invalidated the opponent’s goal:
Usually a raised flag means a goal has been ruled out. This time, a raised flag meant a goal had to be ruled in. Isn’t it ironic ... don’t you think?
[ESPN FC]