Why invest in a balanced scheme?

It helps you in investing in a combination of equity and debt. Essentially a fund manager can design the nature of the fund based on how he wants to achieve various goals he has designed. Typically you have a mix of say 60-40 or 35-65 kind of ratio wherein the fund could invest in a mix of equity and debt.

Typically balanced funds have performed beautifully in our markets. Since they are in a mixture of stocks as well as bonds, they usually give you returns somewhere in the middle of the stocks as well as bonds and therefore you are able to do very well and achieve a good amount of return based on this kind of balanced investing.
The fund manager takes a call and is able to design and implement his call based on market conditions on whether he wants to do more of equity or more of debt. A balanced fund is definitely something you should have in your portfolio.