What is the single greatest piece of career advice? originally appeared on Quora - the knowledge sharing network where compelling questions are answered by people with unique insights.

When it comes to career advice, most people talk about things like getting mentors, picking a boss instead of picking a job, focusing on what you're good at, etc.

This is all good advice. But most people focus on tactics and totally forget the fundamentals. Let me give you two pieces of advice that literally changed my life.

1. Job requirements are negotiable.

I remember going to the grocery store with my (Indian) grandfather when I was a kid.

He would always look closely at the price of everything we put in our basket. And when we got to the cash register, he would do what I thought was the most embarrassing thing ever: he would try and negotiate with the cashier!

I would look away and pretend I was busy with something else as he was trying to get a bargain.

But the crazy thing is ... it usually worked.

Noah Kagan (founder of AppSumo) has this thing he calls the "coffee challenge." Basically you walk into a coffee shop, order whatever it is you want, and when it comes time to pay, ask for 10% off.

If the cashier asks why, say, "Just 'cause."

The funny thing is, most of the time the cashier will just give it to you.

There are so many things in life that we think are "non-negotiable", but in reality, you can totally get around it.

For example, I applied for a business development role once that required 3 - 5 years of experience and I had almost zero (I was still in school at the time).

So I decided to prove to them that I could still bring value. Instead of submitting my resume and sitting back, I decided to go out and pitch some companies on forming partnerships with them, and introduced those companies to the hiring manager. I got the offer.

When I was applying for a product design position at Quora, I ran a usability test on the mobile app, mocked up some design suggestions, and sent it to the head of product design. He emailed me back the same day to schedule an interview.

Apart from jobs like academic professions like medicine or law, job requirements are largely negotiable -- you just have to prove that you can bring value to the table.

I've written in detail about how to do this here: How to Get Any Job You Want (even if you're unqualified)

2. Screw what's "realistic"

What's realistic for you is entirely predicated on what you've been exposed to.

For example, if some high school basketball player told me that he wanted to make it to the NBA, I would think that's totally unrealistic.

After all... what are the odds? Very few basketball players are good enough to get drafted.

But if that same player told Michael Jordan's son that he wanted to make it to the NBA, he would have a totally different reaction than I would. Because for Michael Jordan's son, making it to the NBA is realistic.

It's because his son would know what it takes to make it to the NBA, the work involved, the process behind the scenes, etc. And he knows his dad made it, plus he probably knows others who have made it too.

So to him, it doesn't sound crazy.

Let me tell you a quick story from my own life. My dad's a doctor. I remember when I was growing up, I had some friends who were from lower income families, and their parents weren't highly educated.

They would be like, "Whoa, your dad's a doctor?!" like it was some insanely big thing. In their mind, being a doctor was unrealistic because they just didn't know what went into it.

But I knew exactly what it took to get into medical school, the process behind the scenes, and I had been around people who had successfully done it.

So if someone told me, "I want to be a doctor," I would think that's absolutely a realistic goal. But those other kids might think it's crazy.

There are so many things in life that you take for granted that someone else would think is crazy and unrealistic.

Getting a graduate degree? There's a guy somewhere whose family never went to college, and he thinks that's unrealistic.

Working for a Fortune 500 company? There's a girl somewhere whose family works in minimum wage jobs, and she think that's unrealistic.

Running a multi-million dollar business? There's a kid somewhere who comes from a middle class background, and he thinks that's unrealistic.

Work alongside the best in your field, read their books, listen to their interviews, study what they did to get where they are -- and eventually, those crazy unrealistic dreams will become realistic for you.

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