A lot of pension funds in Europe are trying to convert people to market rate products, where the size of the future payouts are entirely dependent on the market. Most usually claim it is because they can give the retirees more, when the funds doesn't have to be so conservative with investments. In some cases, though, it is also similar to what's seen in the US - there might not be enough money in the coffer to honor the guaranteed interests.
The challenge for pensions in practice is that they are fundamentally either very expensive or very risky, but almost everyone involved pretends like this tradeoff does not exist. People hate uncertainty but few people can afford to eliminate it to the extent they wish to. People want a pension to be "guaranteed" but they do not want or cannot afford to pay for that guarantee either directly or indirectly. This incentivizes both the sellers and buyers of these pensions to engage in willful denial of the financial fundamentals of pensions; they convince themselves the much cheaper product to be almost as good as the real thing because they can't actually afford the real thing. The layer of indirection between the recipient and the underlying securities makes it that much easier to bury dodgy assumptions.
To the extent moving to defined contribution and market products eliminates the popular fiction enabled by pensions, it is an improvement. The actual risk is more transparent to the recipient even if they would prefer to not deal with it.
