A defined benefit DB pension scheme:

A defined benefit pension scheme promises a pension based on a formula, typically linked to salary and length of service. Because the benefit is defined in advance by the scheme rules, members have greater certainty about the level of retirement income they are accruing, subject to scheme terms, accrual rate, and any indexation rules. The investment risk and funding responsibility sit mainly with the employer or the scheme trustees, not with the individual member. This is the key contrast with defined contribution arrangements, where the retirement outcome depends on contributions paid in, investment performance, charges, and annuity or drawdown rates at retirement. Therefore, a DB scheme is not described as being linked to the performance of the assets from the member’s perspective; poor asset performance creates a funding issue for the sponsor rather than automatically reducing the promised benefit. It also does not simply provide an individual “pot” to purchase benefits at retirement, which is a DC concept. Transferability is not a defining feature of DB schemes and, where transfers occur, they are governed by specific rules and may involve giving up guarantees. The best answer is that DB provides clearer knowledge of retirement income.