Most of my fellow students will understand what I mean when I describe the point in time, before a test, when your strategy switches from that of best practice to that of last ditch defence. This is the point where studying (or revising, as it is called here) becomes cramming.
As a strategy, it’s not too bad. There will always be details that you cannot retain in the long term: because they aren’t interesting to you, because they are very specific, or because they just refuse to stick. The revising phase cements the major themes, concepts, and ideas that can be easily remembered in both the short and the long term. The cramming phase sprinkles the desperate remnants on top, where one hopes they will not be jostled off before the exam.