On starting a business
I think you really need to love what you do to start a business or any significant venture because it's probably the single hardest thing you will have to face in your lifetime. So if you ain't obsessed with it and not extremely determined, then you will give up eventually.
On top of that, since determination is where any sizable amount of success is based (probably more than luck and intelligence combined), it's even more important to make sure you love what you do and it is extremely meaningful to you.
To see it from the other side, when you obsess about what you do, you will become this unstoppable machine and you will learn and do whatever it takes to get closer to your mission and goal.
The best part is people around you will start to notice and help you out!
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Also, something that I learned lately is that exponential growth is just constant growth being stretched over a long period of time. So we just need to make sure we are growing every day, no matter how small it is. This applies to everything: customer count, user traffic, books you read, people you helped, etc.