Self-insurance describes a situation in which a person does not take out any third party insurance. The essence of the concept is that a business that is liable for some risk, such as health costs, chooses to carry the risk itself and not take out insurance through an insurance company.
Aim Assist is an option in the Game Options that helps players to aim by slightly locking on to enemies. When a player positions the crosshair over an enemy the Aim Assist helps keep it in place by automatically adjusting the aim as the player and enemy move, commonly known as Sticky Aim.
This is often shunned by snipers, as when coming in and out of scope, Aim Assist will auto-target the dead centre of your opponent, making it troublesome to re-aim for a critical hit. On the other hand others may argue that the auto aim is especially useful in close quarters as it can be used to 'quick scope' an enemy.