Ventajas
Cognizant can be a great place to work at. You have to be self-motivated and driven. You won't often be given a script on how to do your job well. But if you are willing to search for new opportunities, you will find success.
Desventajas
Just like many other tech companies, layoffs are happening all the time. This often brings many projects to a complete halt. Management never communicates when someone is laid off. And when they are laid off, they often never back fill positions, leaving existing team members working the equivalent of three jobs at once. Most teams there are skeleton crews, ensuring that they cannot reach their full potential.