When you consider the police response to actually dangerous situations like a school shooting, what's the point of having the swat gear? They're going to wait

When you consider the police response to actually dangerous situations like a school shooting, what's the point of having the swat gear? They're going to wait until the shooter has shot all of the children at least once and run out of bullets before going in. It's pretty well known that the police have no responsibility to help in a dangerous situation, only to arrest people once the situation has ended