Life is hectic and people are stressed. Sometimes a schedule can change and a different person is dropping off your child. Years ago I worked with a grandmother who took the toddler to daycare on a certain day. One day her daughter needed to drop her off on a day that wasn't her normal routine. The toddler was asleep the entire drive. When she got out of her care she saw her in the back seat. She had forgotten to drop her off because it was not the day she always took her. I can not even describe how distraught she was. If someone else is dropping off your child somewhere, have them call you after the child is dropped off. Also, you can call the daycare and make sure they are there.
I can not imagine how devastating it would be to know you caused harm to a child that you love. I am not passing judgement. Here are suggestions from Parents Magazine on how to prevent such a tragedy. This poster was on the Parents Magazine Pinterest page.