WHY JUICE? IS IT ANOTHER FAD DIET?

It’s been two years since I bought a juicer and started drinking one juice daily, I used to mix fruit and veggies and didn't have a clear idea what it did for me, but I’ve heard that it was great for detoxing and for increasing the intake of fruits and veggies  in a short amount of time. Little by little, as I started to investigate, reading and watching documentaries I realized how vital it is to add veggie juices to your daily diet. But why?