For nearly a year I've been hearing people complain about Rey in Star Wars: The Force Awakens, the number one complaint is that she's able to use The Force without any training. Let me now explain why this complaint is unwarranted and stupid.
Let us remember that Luke Skywalker only received limited training from Obi-Wan Kenobi while aboard the Millennium Falcon, and it was mostly just using the lightsaber. Yet he was able to tap into The Force in order to target the exhaust port on the first Death Star, and also to retrieve his lightsaber in the Wampa cave.
Let us also remember that Anakin Skywalker, as a child, was able to tap into The Force to see things before they happened, thus allowing him to be the only human to compete in Podracing. His Force abilities let him win the Boonta Eve Classic on Tatooine, thus securing his freedom from Watto.
Then there's Leia Organa. Choosing to stay in politics, and presumably never trained by her brother, she was still able to tap into The Force to sense that Han Solo was murdered on Starkiller Base.
So there have been multiple examples of people using The Force without being trained. Training just lets you master those skills, but they are always there; it just depends on how many Midi-chloroxian you have.