The question should not so much be what they don't teach you but what you don't learn at B-school. What I did not learn at B-school could fill up a book, but I think my most important learnings out of business school have been about working with people and making decisions.

It took me a few years to learn that it takes all kinds to make the world, and if I wish to be effective, I must learn to work with them all - the brightest and the best as well as the average and those that do not work diligently.

Many frustrating years later, I have also learnt that just because someone is bright, it does not mean that he is also diligent and will apply himself with integrity to the issues at hand.

On the other hand, I have often been wonderstruck by the earthy wisdom and dedication of many who never managed to get a professional education and graduated near the bottom of the class.

I learnt a lot about decision-making tools at B-school, but learnt only later that in real life, information is almost always imperfect when you have to take a decision. Being a physics student, I loved economics models in B-school.

Real life has taught me that models are wonderful to understand how business might work, if things turn out as predicted. But you can be certain that nothing turns out quite as predicted. Further, nothing that I learnt at B-school was of use in helping me to take a "call" on how to move forward after all the analysis was done.

There are many things that B-schools do try to teach. We were taught by the case method at IIM-A that there are no "right answers", but you must have the attitude and tools to find the right answers.

Further, that it's not enough for you to know what's right, you must be able to convince others. I understood this intellectually at the time, but only now, 25 years later, I am beginning to acknowledge the truth that being right is not only unimportant, it is almost irrelevant if you can't carry the decision makers.