I have not worked for very long in an MNC (only about a year), but I left it for my love for teaching more than an aversion to working in an MNC. Teaching is what I always wanted to do since my IIT Delhi days, so that is the BIGGEST advantage for me. I do what I like to do.
Some of the more objective advantages of being a professor are:
- As Debarshi Banerjee mentioned, you have a lot of freedom compared to MNCs. You are your own boss (without the risk of opening a business).
- Interacting with a lot of young people: You will have 20 year old company even when you are 60 or 70 so it keeps you open to the changes in the newer generation.
- Constant learning: Life becomes monotonous after a few years (few months for me) in a company. You are hardly learning new things. But, while teaching you learn new stuff and in a lot of depth.
- Job security: One is constantly in fear of getting fired in private companies, but in academia, the jobs are more secure and you do stuff out of your passion, not a fear of being unable to pay next month's rent or mortgage.
- Independent research: One can do research in whatever topic they like, e.g., if I want to do research in biology or psychology, although I am an electrical engineer, no one can say, "No you can't do it."
But, one should be careful while making this career choice, because once you go into academia, you become unsuitable for industry consumption (as an employee, although they may still want you as a consultant). It will be harder to find an industry job because it is harder to control you as compared to a person who has worked in industry all his life.