Why should we join NIT Raipur? Everybody says that joining NIT Raipur is a waste of time because people don't get jobs after.

The question you should ask yourself is whether you can drop another year for your JEE preparation or not. If you are confident enough that you can rank higher in your next attempt and get a better college, you can definitely reject NIT Raipur. 

However, to think NIT Raipur won’t provide you with any jobs is incorrect. Though it is a tier 2 college and does not offer the same opportunities as top NITs, getting placed depends more on your hard work and caliber. Even IITians end up without jobs at times. So you have to take your future in your own hands. If you have the skillset you’ll get placed off campus if not on campus. 

Research about the branch you are getting at NIT Raipur, learn about your career prospects, and prepare accordingly. You can also join the institution and still give your next JEE Mains attempt. 

Thus, joining NIT Raipur is not a waste of time. You’ll have to learn to make the best use of its resources and facilities.