He means you have to research into yourself... And figure what do you WANT or have a BURNING DESIRE to do! If you go at the 'present opportunity', which may not as well be what you WANT, you may regret later that you didn't do what you wanted to do.
i don't totally agree that you always regret, it's not always too late,
one of my fathers friend was a doctor and is now works with computers,
we asked him why he said he worked in a thailand hospital in special section where they
bring immature babies and a lot died so he got tired of blood and know is some type of computer guy.
you read about different people, i heard about a egyptian man who liked journalism but went into medicine for
his parents wishes but he worked both at the same time, then a law was was stated that you could have only
one job, he chose journalism.
I still dont know what i want to do?