Everything is, because it is the only correct and logical thing to be.

Starting from the universe and its beginning, all the things that reside in the universe, the way everything functions, the way everything is, when everything is, where everything is, how everything reacts, everything that exists and the way it exists and acts, is because it is the only correct and logical thing for it to be.

Lets take for example, the law of gravity. Smaller objects get attracted to the larger ones because of the dent that the larger ones create on the fabric of space time than the smaller ones and the smaller objects can't do otherwise than to go down the dent that the bigger objects created.

When we look at the example above, we can see that it is the only logical option that it had. Thus it was the only logical and correct thing for it to be like so.

It is only logical for a wall that is stronger than your push to push you back when you push it, it is only logical for it to tumble down if it is not strong enough. It is only logical for water to turn into ice when it is cold enough, and to turn into vapor when it is hot enough.

So believe it or not, the same goes to all things from beginning up till now and the future and things we don't understand yet. The answer to all of them is that it is the only logical thing to be.