Because they have no understanding of WHY you have projects laying around that are nearly finished. And they insist you drag them out and get them done.
Thanks to our resident nagger (that would be Cara), I have finished the Dale of Norway Sirdal Cardigan that has been sitting in a bag for 2 years. And it's really beautiful. Although I did mess up the buttonhole placement a bit. But I'm not fixing it. That would relegate the sweater to the bag for another 2 years and Car would never stand for that.