It tastes like mud. Surely something that disgusting is good for you?
There is no correlation between something tasting "bad" and being good for you. Many things that taste bad are in fact bad for you, and many things that you think taste bad, other people like the taste of.
When you juice a vegetable or a fruit, the taste is generally stronger in the juice than if you were just to eat it raw. If it's a cherry or an orange, that's considered a feature. If you don't like the taste of beets, then juicing them isn't going to make them taste nicer. However, it can put them in a form where the taste can be hidden - by adding sweet fruit juices, by adding crushed ice (cold reduces the taste of most things) and the like - or it won't last long because you can drink it quickly compared to chewing and swallowing a quantity of solid food.
Like all vegetables, beets can be part of a healthy diet. But there is no single vegetable that must be eaten to ensure health. People all over the world go their whole, healthy lives without ever eating a beet, raw or cooked. You didn't specify what health benefits you feel it provides, but I suggest researching a little to find a different vegetable that will give you those benefits with a taste you enjoy. You could also (depending on the benefit you're looking for) consider cooking it differently in the hope of finding a preparation you enjoy. I love borscht made with lots of bacon, onions, and potatoes, and topped with sour cream. I also like dried beet chips topped with sea salt, and grated beets fried in butter with a squeeze of lime juice and some lime zest (a dish we call "Surprise! You Like Beets!" at my house.) But if you don't like them, eat something you do like. There are no medals for eating unpleasant things.