Everybody is decluttering right now; that's the national chore in January. Everyone knows who Marie Kondo is. Everyone my age and older is familiar with FlyLady. My mom and her group of ladies had Don Aslett to read for inspiration in decluttering. (By the way, he's my all-time favorite author on the subject. Humorous, and leaves the reader with no excuses for hanging on to junk.)
All this has spurred the thought that "use it or lose it" applies to much more than muscle mass, agility, and cognitive abilities. (Speaking of cognizance, I was having trouble even thinking of that word...)
Have you noticed how quickly houses fall apart when they're vacant?
Crystal becomes very brittle when it's not used and washed in warm water routinely.
Plastics become brittle, too.
Cloth and rubber dry rot.
Wood and paper products get musty.
Motors and gears rust; batteries bust.
Bugs and vermin creep in and leave a path of destruction.
Lack of airflow (life) causes mold and mildew to form.
Only a museum is equipped to keep unused things pristine.
Stuff likes to be used and loved. Even though material things wear out with use, no use at all will also wear it out.
To take this in an another direction, the same thought applies to finances. Money has to be told what to do. We have to learn about and understand retirement funds. Money won't just stick around because it's needed later. Accounts have to be monitored. I know a widow who is battling senility and blindness now, has massive amounts of wealth, and can't find the will for her estate. The lawyer who drafted the will is dead. She was very careful throughout her life to keep others out, and now when her family would like to help her, the state has stepped in to "help" and is keeping the family away from her. Most likely, the wealth she has amassed will end up going in whatever direction the state determines, unless by some miracle, that will is found and is still applicable.
Back off that rabbit trail, the point is that all our resources, material and immaterial, must be tended to give their full benefit. Give up those things that aren't needed anymore, and start paying attention to and using what will give joy with the use.
We aren't taking that china or fancy furniture with us when we die. Use it or lose it.