I think with the examples you gave there is likely a mixture of reasons (excluding dementia as one of them though). With housework children just don't do as good a job as parents. When my kids vacuum they don't pull out the furniture of get alongside the walls like I do. That's not dissociation or poor memory, but inexperience. Setting a boombox on top of a stove burner you didn't know was on... inexperience. Kids do stuff like that because they haven't had enough experience to predict outcomes. Some other stuff you mentioned is likely normal memory stuff, and some other things sound like they could be dissociation related.