So, what's happening during this processing time that makes pickles so... pickle-y? It all comes down to science - specifically, the process of fermentation.
As the cucumbers sit in the brine solution, tiny microorganisms start to break down the natural sugars in the vegetable, producing lactic acid and giving the pickles their sour taste.
It's a pretty cool process, and one that requires patience - after all, you can't rush a good thing (or a good pickle, for that matter)!