I see the inside of maybe 300 homes a year. Many if not most homes do not have enough storage space, possibly because the occupants have too much stuff. That is why rental storage spaces have become so popular.
Storage lockers can be very handy for home sellers who can remove excess furniture and possessions from their house and store them.
When I needed to move my parents I rented storage space because it gave us some flexibility and time to figure out what to do with excess stuff. I just couldn’t make decisions fast enough as I prepared their home for sale.
Rented storage space is also nice for people who move often.
Personally, I think having less is best but that isn’t always easy to achieve.