In some cases, parents do not want to leave their homes to their children. They feel like it would just be a burden for the kids to have to decide if they want to keep it or sell it -- not to mention going through with the sale and splitting up the money. It can even lead to estate disputes.
If you decide to use a trust for your assets, it can prevent the children from using those assets in the way that they want. For instance, a trust could stipulate that the child does not get any money until age 30 or that the money has to be used to pay for college tuition.