UPSC IAS Prelims Previous Year Papers (PYQ) - Yearwise and Subjectwise

5 reasons why PYQs are a must-

1. Only through PYQs you get a clue about what and how UPSC is thinking. Without PYQs you will keep working on your own assumptions and that will not yield results.
2. You understand the high-priority themes for UPSC. You can’t be studying like an 11th or 12th grader and then expect to clear the exam. These are not boards.
3. Within those high-priority themes, the depth and dimensions being asked are very important. You have to closely observe them.
4. Undertanding question framing, options.
5. Attempting PYQs means simulating real exam conditions. Each question will appear like a bouncer. But can’t duck. You need to take shots.
 

Every topper has attempted UPSC Prelims PYQs multiple times. And each time they attempt the paper, they get something new to learn from it. This is what makes it mandatory. 

Attempting PYQs is step 1. Analysing PYQs is step 2. A good methodology is to leave detailed notes in the comments of each question as you attempt. These notes will help you review your attempt