Are your twenties prime time to postpone worrying, kick back with a margarita and just enjoy life? Or are there ‘harsh’ life lessons you simply must experience before you reach 30 to be successful?

BBC Capital went to question and answer site Quora to find out the most difficult lessons it might be best to learn young.

The internet of non-friends

Quora user Max Lukominskyi, chief marketing officer at Sliceplanner, suggested it’s crucial to learn that “online friends are fake friends,” he wrote. “Unfortunately, yes. Most of them do not care about you and will not come in your hour of need.” He wrote that experience and emotions will end up as your “best investments”, adding that traditional measures of success  —  fancy cars and houses  —  are no longer  relevant.

If you let them see you sweat

Charita Johnson wrote that it’s important to know your own weaknesses. Better to do it young  because you will learn the world will be “quick to try to exploit them”.

Give up on shortcuts

"There are no magic lifehacks to become successful overnight,” wrote Yuri Kruman. “You have to hustle constantly, sell yourself to everyone you meet, tell a good story and always know how to get your point across to every audience."

Be well-spoken if you want to go far. That means learning to get to the point

Another hard truth: mastering a skill or job takes a lot longer than it seems, and just becoming conversant isn’t enough, “especially when you’re surrounded by other brilliant, motivated people that have been doing what you want to be doing for years.”

Be well-spoken if you want to go far. That means learning to get to the point. “The one thing busy people can’t stand most is rambling,” Kruman wrote. “Make your point and move on.”

Test your limits

Going beyond your limits in your twenties is crucial. It helps you learn to control your impulses, wrote Stefan Papp. “If you [learn] this lesson young, in older age the risk is low that you think you missed something,” wrote Papp. “I know a lot of people in their forties and older who think they missed something when they were young and try to now to be young again.”

Going beyond your limits in your twenties is crucial. It helps you learn to control your impulses

Nick Johnson, a neuroscience PhD student, wrote that the real challenge in your twenties is learning to navigate the contradictions in all the advice you’re given. For instance, “‘no one will help you’ contradicts ‘your real friends are there in your hour of need’.” Johnson suggests that these are all good bits of advice, though, “if given at the right time by someone wiser than you”. The hard lesson: learning when to follow which.

Quora respondents are required to use their true names under the site’s Real Names policy. To help ensure legitimacy and quality, Quora asks some individuals, such as doctors and lawyers, to confirm their expertise.

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