I do this whenever I’m squirting something out of a squeeze bottle with a nozzle, like shampoo or hair gel, and I squirt out too much. I squeeze the bottle (with it upright so nothing comes out except air), stick the nozzle into the blob of shampoo or gel or whatever, and then release the bottle to create suction at the nozzle which sucks up the excess stuff.
I was wondering if anyone else does this! If not, you should. You’ll get a strange feeling of satisfaction! (At least I do.)