Take education. Whether or not you pay directly for it, it's expensive. Even if, as a child, you don't have to fork out for it personally, the years between 18 and whenever you finally finish burning couches could have been filled with making money. Instead you get a piece of paper at the end that says, well, maybe, that you might be worth more than the next snotty applicant.

What if you go through all the hard work but don't get the high income because you become disabled?

Insurance could help.

This is how insurance is connected with investment. Usually any investment requires you to take a risk, and risks can be covered.

KiwiSaver is like that too - you lose 2% to 6% of what you could have had in your pocket or as extra remuneration and you stick it in a fund where you can't get at it. It's not as useful as your other savings because you can't borrow against it, you can't borrow some to meet unexpected bills, and you can't do anything with it until you are 65 (presently, maybe older...)

Here's a recent case of a KiwiSaver investor:

...a member who had a brain haemorrhage and now suffers seizures and can't work or drive was twice refused permission to withdraw his KiwiSaver money under the serious financial hardship and serious illness clauses. On his third attempt, with the help of a consultant and some media attention, the trustee approved the withdrawal...

You can imagine how much was in the KiwiSaver can't you - probably less than $10,000. That won't last long. A little income insurance - even just $30,000 a year paid after 90 days wait would have been enough to make all the difference.

Right now I reckon that there's about 800,000 people who got their KiwiSaver by default and for most of them, when they stop working, so will their KiwiSaver.