If you’re continuing to sort through the contents of the storage space (or a room in your home) that you’ve been working on, consider why most of the items that you’ve identified as unwanted have ended up in this space.
If you were holding onto items “just in case” reframe this as “when could I use this?” If you were convinced that you would use something in the future because you used it in the past (say, ski equipment that’s gone unused the past couple of winters), set a deadline for using the items (“my goal is to go skiing during winter '20-'21”).
If the deadline passes without using the items, it may be an indication that your life has changed and it’s time to let go.
Of course, you can question any item in your home this way, not just items that are in the attic, basement, or garage. Do you have a lot of things from previous hobbies and interests? Check out this article on decluttering this group of items.