Why does the economy grow in the long run?

Why does the economy grow in the long run? This is a really tough concept to grasp for me.<br><br>*Why* does the economy grow? A lot of people say that productivity increases, i.e, technology improves and that allows us to produce more with the same amount of inputs. <br><br>But why does productivity increase? I.e, what even drives technological progress? Why does technological progress happen at a faster rate than population growth?<br><br>Why does the economy grow at a rate of 2% every year? Why doesn’t it just grow by 1% every year?<br><br>Why? Why? Why? Why?<br><br>Please help me out.