Ellen, if you were paying into a savings scheme in a bank, you would (unless the bank went bankrupt) get what you put into the bank plus any interest the bank had earned on your behalf (from interest earned on lending your money to other customers, plus investments).
A pension scheme is the same in that you are putting money into it BUT you are expecting to get a SHED load more out of it, which you hope the pension scheme can earn through investments, but the return on these go up as well as down, as we all know, depending on the economy, skill/luck of the fund manager, and how much is left in the pot once everyone else has taken their share. So you could end up with much less than you expect. In fact you may end up with less than you put in (if you're in a Defined Contribution scheme) if you've not been in it very long and end up being charged admin fees that are more than the interest earned.
So actually, it's quite different. Cash savings are low risk, investments are higher risk.
The economy is not good currently so investment growth is less than in previous years and not meeting our previous expectations, hence the need to put more money in if we are to meet those expectations. Question is, if the money's not coming from investment growth, where's it coming from? Tax? Education funding?