In my experience, I have found that there are one (or more) of three reasons when the Law of Attraction doesn't work.
First, and by far the most common, is that we effectively and most often unknowingly change our mind. If you are looking for a relationship in your life, you can readily picture the person you are looking for with exactly the right traits, interests, etc. Then, you hold that picture in your mind. You have the active daydream of sharing with that person in a wonderful, loving relationship. You have done it all perfectly. You are sending out the right energy and it is accumulating for you. But then in a weak moment, you might think "Oh, he/she won't come. I'm too____ (ugly, old, short, dumb, whatever). Well, there you go...... The Universe loves you so very much it WILL give you want you want, and what you want must be what you are thinking about. So if you are thinking that someone won't come because you're dumb, then very lovingly the Universe will keep them away and at the same time put you in a situation where you can experience being dumb. You may not think so, but that is the most wonderful, loving thing you can receive! You have gotten what you are thinking about. Another example: Simply thinking that you want someone because you are lonely will keep them away. Because your primary thought and where you are spending your energy is dealing with "lonely". So that georgeous, wonderful, precious Universe will lovingly give you what you are focusing on -lonliness.
The second reason the LoA might not work is because you have some special life purpose that is contrary to what you are wanting to manifest. It may be a lifetime purpose that you are to do or experience or possibly karmic repercussions that you want to clear up this time around. It may sound morbid or wierd, but you could have given yourself the experience of cancer for any myriad of reasons (compassion for others, need to receive nurturing from others, experience the current treatments for cancer, or, a biggie, be there as a support for someone else suffering the same way). Under these circumstances, all of the perfect steps you perform using the Law of Attraction to eliminate the disease won't work. Because on a soul level you did indeed want to experience what you are currently experiencing.
The third reason for the LoA not working, is the concept of Divine Timing. You may be doing everything right and the Universe wants to help and bring it to you, but for some reason it just doesn't seem to be happening. In this situation, Creator knows. I want to say this just that bluntly. Creator knows. But Creator also knows what is the very best not only for just you but for all of humankind. Imagine the Universe beautiful and just and perfect. Then be sure of one thing: Creator has imagined it quite a bit better than you have. Your manifestation will come - at the best time possible.
So.......... You want to win the Lottery and it isn't happening. Do you think deep down that the odds are too great to win or that you "hope" to win (which is the same as not winning)? Has your soul chosen to experience a life without noteriety and/or luxury? Or maybe, it will indeed be yours, but at just the right time when you can use that lottery to do the very best you can for all of the world. Please remember, though, that all of these reasons for not winning are perfect and flawless. The world is yours to create for you and you are doing exactly that. Congratulations on a job wonderfully well done!
Love and peace to you always,
The Old Monk