The general principle is, the higher the risk, the higher the premium.
By paying an excess, you are accepting the management of a small part of the risk and thus you will pay a lower premium. You may also choose not to pay excess, this will translate to a larger premium since the full cost of the risk has been transferred to the insurer.
Indulging in risky behaviour may be excluded from some forms of insurance. For example, most medical insurers may not accept claims from bungee jumping or sky diving injuries. Motor insurers are unlikely to pay your claim if the driver of the vehicle was involved in an accident while driving under the influence of alcohol
