I believe the number one responsibility of any parent is to prepare their children to become independent self-reliant contributing citizens of society. This entails providing a healthy positive environment that encourages building self-esteem and discipline. Children who have chores are taught responsibility and learn the value of working and accomplishing a task.
One of the worst things is seeing an (adult child) who does not know how to do basic things such as cooking, cleaning the house, ironing, and doing laundry. These are things that both genders should be taught over the years as they grow into adulthood. If an adult child is still relying on their parents for these basic things the parents have failed in my opinion.
After a certain age parents shouldn't be treating their children like hotel guests! I knew a teenage girl who never hung her clothes up. She'd either leave them on the bed or floor for her mother to put them away. She told her mother what she wanted for dinner, left her empty plate on the table, and was not expected to do any housework. Her parents were nothing more than servants, chauffeurs, and human ATM machines. (And they loved it!)