Why timetables built on an empty week fail
Most planners hand you a blank grid of seven days and let you fill it in. The result is a week that only exists on paper: revision at nine on Monday morning when you are in a lecture, and a three-hour block on Wednesday evening that you spend commuting home. The plan fails on the first day, so it gets abandoned by the third.
Here the blocked hours go in first. Lectures, practicals, a coaching class on Tuesday and Thursday, a part-time shift, ninety minutes of travel each way — all of it comes out before a single study session is placed. Whatever is left is your real budget, and it is usually smaller than you assumed.
The arithmetic is worth doing once. A week holds 168 hours. Take out 56 for sleep, 20 for classes, 10 for travel and 21 for meals, chores and the rest of life, and roughly 60 remain — of which nobody studies more than half of them well. Planning 40 hours of revision into that week is planning to fail.