There could be many things that fall into this category. For starters, consider all of the proposals that we made where we never got a response. How about all of the voice mail messages to various people that were never acknowledged or calls returned? Could be they don't want to talk to us - no matter because we aren't able to talk with them anyway.
Maybe there is unread mail piling up on our desk - from several days or even weeks ago. We know it's not urgent or important - that we would have looked at. The rest is not capturing our attention so it's time to move on without it.
Grudges, slights, disappointments, and other bumps in the road that have concerned us this past year or otherwise gotten in the way of our progress can be set aside as we move on without them. This is the time to bid "good riddance" to them.
Items that we have collected because they looked worthy of our interest but somehow never rose to the level of importance that actually cause us to need or use them may not need to be retained any longer. We may not just want to dump everything in this category, but we certainly can begin to weed through it and toss what clearly is no longer of any interest or need.
Brochures or other literature that we collected this year on the chance that we might want to learn more about it or act on what was proposed may not be needed any longer. Again, some items may wish to be retained a bit longer, but many likely can be discarded.
Coupons - online and physical copies - that have an expiration date before today obviously have no more value so we can toss or delete them.
There's a strong chance that items that we flagged last year on "Good Riddance day" that we have not looked, needed, or used since don't need to be retained. This is not for all archived or historical items but just those that already were identified as potentially unnecessary.
Going through the supply cabinet and pantry and looking for expired items to discard will free up space for items that can be acquired and used.
Of course, not everything that we "discard" will end up in the trash. Some can be resold on sites like eBay or Craigslist. Some might find their way to a consignment shop. Others are going to be given to a thrift store as a donation sop that a charity has a chance to make money from our serviceable but unneeded items. Some can be recycled through our local government or charity program. Some items can be given as a straight donation (with or without any tax purpose in mind) to non-profits or individuals that can use such items.
As we close the book on 2016 and get ready for 2017, this is the time (and it may take more than just one day) to set aside anything that is no longer needed or anything holding us back to free us for future activities.