Imagine if everyone had the power to make anything they wanted happen. You could get a job you want, get someone to sell their house to you at any price you want, make someone fall in love with you, move the stock market to make a company shares go up or down because you want it to go that way, or even win the lottery,
This means you are playing God and the entire world should go the way you want it to go regardless of everyone else and what they want. Guaranteed someone is going to want the opposite you want, or perhaps also want to get the same job or house. Why should you get what other people also want?
Then imagine the battle that would go on in the world, all the people pulling everything in different directions. Where is freedom of choice or right to life? The concept of LOA means you can control so many other people and make them do what you want because the LOA says you can have anything you want. Have you thought about that when you make your vision board?
To imagine that you can use the LOA as you wish to get whatever you want, and it is as simple and wanting, implies that you are powerful enough to make every other human being simply a slave and robot to fulfill your commands.
Having said all that, I have found the LOA mentioned in the Hermetic teaching of over 3000 years old, so the principle is ancient and real, and if you knew the things that happened in my life, then the whole world should come to me to learn how to use the LOA.
The trick is to use the laws of the universe in a humble and fair way such that no one is hurt or controlled in a negative way to fulfill one person's ego or personal desires.
There are also a lot more things one must do that the modern false teachers and 'The Secret' do not talk about because of the hard work involved to make the law work for you. But first, your heart and mind must be pure.
Your intentions and desires must be of a nature that is beneficial to all beings and your intentions must be to use what you get in a useful way to more than just you, because there is a guy who appears to have mastered the law to a great extent, actually a few of them, who had self-centred, egoistic desires; Hitler, Stalin, Mussolini, to name a few. On the other hand, Gandhi, Andrew Carnegie and Napoleon Hill have also mastered the LOA.
If you get the power and your heart is not pure, you see what can happen. This is why the LOA is effectively useless to the masses and most people, by good design, a safety feature.
If you believe in this law, and you know it can work for you, then first you have to really learn how to use it, and that is be making yourself worthy of it working for you. Then choosing the right things to attract, and carefully consider what you will do when you get them.