Kicking a common habit could help boost your career, says Estonia's youngest-ever inventor

Karoli Hindriks, founder and CEO of Jobbatical.

If you want to have a successful career, it can be tempting to try to be all things to all people. But, instead, you should know where to draw the line and be unashamed about saying no.

That's according to Karoli Hindriks, who, with a resume of accolades including serial entrepreneur, European Parliament speaker and MTV's youngest-ever CEO, is a success story by any standards.

However, it's a lesson she learned the hard way: When Hindriks founded her first business at 16 — a line of reflective accessories for pedestrians — she became Estonia's youngest-ever inventor and found herself suddenly in high demand.

"With my first business, I became so famous so fast," said Hindriks, whose young success saw her invited to speak at countless schools and entrepreneur forums.

"I ended up spending more time talking about my business than running it," Hindriks told CNBC Make It at "Women's Forum Singapore."

Karoli Hindricks, founder and CEO of Jobbatical.

The celebrity gave Hindriks exposure and launched her into her next career, spearheading MTV's expansion into Estonia as national CEO. But it caused her business to fall by the wayside in the process,

"None of these things were improving me or my business, but they were diverting my time and attention away," Hindriks noted.

Knowing when to say no

That's a mistake the now-35-year-old is determined not to make with her new business, Jobbatical — a recruitment site for international job placements. And it's advice she shares with her applicants.

Now, whenever Hindriks receives business requests, she asks herself three simple questions:

  • Will it help my business?
  • Will it help my family?
  • Will it help myself?

If the answer to any of those questions is yes, she'll accept it. Otherwise, she'll pass.

"It might make me sound mean, but I know I'll be a better mother, CEO and person, generally, if I know where to draw the line," said Hindriks.

Even now she still finds it difficult: "It's hard and I'm still learning," said Hindriks. But that criteria has also helped her get creative with her time management so she can say yes when the right opportunities arise.

For example, if she's offered a business dinner, she may request to make it a lunch to free up time in the evening to spend with her young daughter, go for a run, or simply have an early night.

We all have limited availability, said Hindriks, so "you should really focus that time on what you care about and making a difference with it."

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