Or to put it slightly more impolitely what pisses you off?
What makes you angry about the world? Think about this and you will have a subject that could animate both you and your photography. When you are angry about something you learn about it and develop ideas about it.
For me, while not angry about it I have a real fascination in how capitalism functions, I have read about it from so many perspectives and still, I feel I need to know more about how it functions. Yes, I have read books by and on Marx, Smith and Keynes and many more, analysing how capital is created and its used, etc. I have however, come to the conclusion that our greed (both individually and collectively) and capitalism, may have become a dangerous combination for survivabilty of our species on planet earth. Why do our rich not want to change course? This is something that I for a long time I could not understand, but then again, I realise that we as a species do suffer from short termism and self interest.
But that is my interest, what is yours? This is where you can find the motivation get out and make your own work, as a photographer. Find what you are passionate about, I believe that you already know a lot about it and have strong opinions about the subject, go and do some more research and then work out is the subject something that lends itself to being photographed. If so then it is easier, if not, then look at how you can make it into something that is possible to make images of.
This is what it takes to find a subject to make work on you need to be passionate about what you do, the other side of this is.
What do you love?
What activities or subjects do you love, and again you will know a lot about them, because you are interested in them. These to aspects can lead you into being able to make work that you are passionate about, and from that it becomes possible to make work with the dedication, and determination that good projects and work takes to make.
So stop procrastinating and go and start the research on what you are going to do next. As a creative person finding what you hate and what you love could be the key to making work that really motivates you and leads you to make the work you have always wanted to make.