Annuities provide a stream of payments and are generally classified as insurance because they are issued by insurance companies, are regulated as insurance, and require the same kinds of actuarial and investment management expertise that life insurance requires. Annuities and pensions that pay a benefit for life are sometimes regarded as insurance against the possibility that a retiree will outlive his or her financial resources. In that sense, they are the complement of life insurance and, from an underwriting perspective, are the mirror image of life insurance.
Certain insurance products and practices have been described as rent-seeking by critics. That is, some insurance products or practices are useful primarily because of legal benefits, such as reducing taxes, as opposed to providing protection against risks of adverse events. Under United States tax law, for example, most owners of variable annuities and variable life insurance can invest their premium payments in the stock market and defer or eliminate paying any taxes on their investments until withdrawals are made. Sometimes this tax deferral is the only reason people use these products. Another example is the legal infrastructure which allows life insurance to be held in an irrevocable trust which is used to pay an estate tax while the proceeds themselves are immune from the estate tax.