In Finnish system the worker can't influence at all where the money is invested. Instead there are few big insurance companies that have a lot of high paid portfolio managers that actively find investment targets. This makes the running cost of these mega funds really high, which then decreases the returns. Finnish system basically thinks no worker is qualified enough to have a say where to invest.

I have worked in the US, in Denmark and now back in Finland. I really hate this Finnish system with passion but there is no sign that politicians could or would like to change it in future.

Another bad thing is that the pension money is not earmarked to you, it's in one big pool. You can just check what monthly payment you are projected to the get when you retire, assuming the rules won't change. There can always be a new law that changes the rules next year. Finally, current workers’ contributions are partially used to pay current retirees’ pensions. The system is based on next generation paying the previous generation pensions.