I think the "can't find it" is the defining moment. My garage, which is actually more of a workshop, used to be nicknamed the TARDIS, i.e. it seemed to hold much more stuff than the the external view of its size would indicate. Eventually I hit the defining moment once too often, so I threw out everything stored but not used in the last five years, then narrowed that down to three years, and eventually just a year. Now I have a fair amount of "free" space, which is great. I also no longer struggle to find stuff, because it's not there, I threw it out and now have to go out and buy it...again. The one truly good result is that I can now see and use the workbench again but thanks to inbuilt obsolescence there's rarely anything to fix.
Pre-order your recycled pallet wood bird-box here...