Cleaning can take a really long time if someone doesn't know how to do it right. There are also two types of clean - the appearance of clean and actually clean. The appearance of clean means stuff might look alright on the surface but if you look too closely it might really be dusty or someone might have just take a bunch of dirty stuff and shoved it into a closet. Actual cleaning takes a bit of time to learn how to do. It means taking everything off of a bookshelf, dusting it and cleaning stuff as you put it back on the shelves. It means getting on your knees and cleaning the whole toilet, not just the inside of the bowl. When Chris made videos to show the progress of cleaning his room a lot of it was just moving stuff around and it did actually look better but I doubt he has any idea of how to really clean anything. That makes me feel very, very bad for him. Not everyone who grew up in a dirty home will learn how to clean properly as an adult so it's doubtful the house will ever be truly clean, even if they threw out a bunch of the junk.