GOOD QUESTION – One time I designed a ‘counterbalanced lifting beam’. We were trying to lift something out of a pit BUT we couldn’t access the area vertically above the object (i.e. we couldn’t get a crane in there).
My idea was a counterbalanced beam which had a counter weight on one end, and then the object we were lifting on the other so the thing balanced like a see-saw (hopefully this makes sense). The beam could then be held by the crane in its centre, where there WAS crane access.
The heavy gang (the people who do the heavy lifting around site) didn’t like it (they said it was dangerous) and it was never used!