1995 Oldsmobile Cutlass Cutlass won't turn over - battery c

Starter doesn't turn over. Headlights dim all the way down.

Began to crank slower over past three weeks.
Last time so slowly that I drove around, but then after returning, it cranked right up.
Next day starter wouldn't turn over at all.

Screw on battery terminals were tight and not corroded; 40a starter fuses are good.

Took Battery out for load test. They put it on a machine for 30 minutes and said it was good and now fully charged.

Immediately put it in but no change. (Not turning over, headlights dim all the way down)